Search references for DECSYSTEM 20. Phrases containing DECSYSTEM 20
See searches and references containing DECSYSTEM 20!DECSYSTEM 20
36-bit computer by Digital (1966–1983)
Digital Equipment Corporation (DEC)'s PDP-10, later marketed as the DECsystem-10, is a mainframe computer family manufactured from 1966, delivered from
PDP-10
Type of mainframe computer
The DECSYSTEM-20 was a family of 36-bit Digital Equipment Corporation PDP-10 mainframe computers running the TOPS-20 operating system and was introduced
DECSYSTEM-20
Series of server computers
large pedestal cabinets. The DECSYSTEM name was used for later models of the PDP-10, namely the DECSYSTEM-10 and DECSYSTEM-20 series. Identical to the DECstation
DECsystem
Operating system by Digital Equipment Corporation
Manual was described as for "DECsystem-10/DECSYSTEM-20 Processor" (meaning the DEC PDP-10 and the DECSYSTEM-20). TOPS-20 began in 1969 as the TENEX operating
TOPS-20
Name used for several lines of minicomputers
PDP-15 12-bit: PDP-5 → PDP-8 → PDP-12 36-bit: PDP-6 → PDP-10 → DECsystem-10 → DECsystem-20 16-bit: PDP-11 [→ 32-bit: VAX] PDP-1 The original PDP, an 18-bit
Programmed_Data_Processor
Character encoding
four additional bits into one 36-bit machine word (PDP-6, PDP-10/DECsystem-10, DECSYSTEM-20), three characters plus two additional bits into one 18-bit word
DEC_RADIX_50
Topics referred to by the same term
Cyberpunk 2020, a cyberpunk role-playing game DECSYSTEM-2020, a model of computer in the DECSYSTEM-20 line The 20/20 Experience, an album by Justin Timberlake
2020_(disambiguation)
American electrical engineer and political activist (born 1934)
Apple II, including PDP-11/20 minicomputer in 1969, Datapoint 2200 in 1970, IBM 5100 portable computer in 1975, and DECSYSTEM-20 in 1976. Holt later joined
Rod_Holt
Dialect of the ALGOL-60 for systems programming
It was originally a large ALGOL 60-like language for the PDP-10 and DECSYSTEM-20. The language combined the earlier PDP-6/-10 language GOGOL compiler
SAIL_(programming_language)
advertisement for a presentation by Digital Equipment Corporation for their DECSYSTEM-20 products written by Gary Thuerk, a marketer of theirs, and Carl Gartley
History_of_email_spam
Assembly language
facilities for DEC's PDP-10-based Mainframe computer systems, the DECsystem-10 and the DECSYSTEM-20. MACRO-10 is implemented as a two-pass assembler. A simple
MACRO-10
Computer architecture bit width
the Digital Equipment Corporation PDP-6/PDP-10 (as used in the DECsystem-10/DECSYSTEM-20), and the Symbolics 3600 series. Some smaller machines, such as
36-bit_computing
1977 video game
company's president. The core game was complete, but it had been run only on DECSYSTEM-20 and PDP-11 mainframe computers. Infocom purchased a TRS-80 personal computer
Zork
Computer architecture with addressable bytes
Vol. I (5 ed.). Stuttgart, Germany: Gustav Fischer. p. 125. DECsystem-10/DECSYSTEM-20 Processor Reference Manual (PDF). Digital Equipment Corporation
Byte_addressing
Company that provides business services for a fee
computer services. Although Landart Systems, Inc (LSI) opened in 1973 as a DECsystem-20-based timesharing bureau that also did computerized typesetting, it was
Service_bureau
Software feature
"Origins and Development of TOPS-20". www.opost.com. Archived from the original on 2020-08-01. Retrieved 2006-09-10. DECSYSTEM-20 Assembly Language Guide "Working
Command-line_completion
1982 video game
of ARPANET.[citation needed] It was first written in Maclisp for the DECSYSTEM-20, then ported to Emacs Lisp in 1992. Since 1994 the game has shipped with
Dunnet_(video_game)
American computer manufacturer (1957–1998)
factor). Unified product line upgrades produced the compatible DECSYSTEM-20, along with a TOPS-20 operating system that included virtual memory support. The
Digital_Equipment_Corporation
American company that develops optical transport network technologies
TD-1, was announced in 1993 and built as an extended version of the DECSYSTEM-20 from Digital Equipment Corporation. The original inspiration was to build
XKL
1969 operating system by BBN
but did not end up being any lower in cost. From the start, the new DECSYSTEM-20 would run a version of TENEX as its default operating system. Functional
TENEX_(operating_system)
36-bit mainframe computer (1964–1966)
al. 1978, pp. 487, 489: "The project from which the PDP-6, DECsystem-10, and DECSYSTEM-20 series of scientific, timeshared computers evolved began in
PDP-6
American computer scientist
TOPS-20 operating system, an evolution of TENEX for the newer models of the PDP-10 family. TOPS-20 was first marketed in 1976 on the DECSYSTEM-20. Daniel
Daniel Murphy (computer scientist)
Daniel_Murphy_(computer_scientist)
List of programming languages types and the languages that meet its description
PDP-4/PDP-7/PDP-9/PDP-15 12-bit: PDP-5/PDP-8/LINC-8/PDP-12 36-bit: PDP-6/PDP-10/DECSYSTEM-20 16-bit: PDP-11 (influenced VAX and M68000) 32-bit: VAX 64-bit: Alpha
List of programming languages by type
List_of_programming_languages_by_type
American video game designer
Brian Moriarty Brian Moriarty stands beside Infocom's DECSYSTEM-20 mainframe (1984) Born 1956 (age 69–70) Occupations Video game designer, Professor Known for
Brian_Moriarty
File transfer protocol
floppy disks at various microcomputers around campus, such as IBM or DEC DECSYSTEM-20 mainframes and Intertec Superbrains running CP/M. IBM mainframes used
Kermit_(protocol)
1982 monochrome laser printer
Xerox 9700 could also be used in off-line mode in conjunction with a DECSYSTEM-20 mainframe computer, as well as with a Honeywell DPS-8 mainframe and DEC
Xerox_9700
1960s computer collaboration system
Attempts to port NLS to other hardware, such as the PDP-10 and later on the DECSYSTEM-20, were successful. It was transported to other research institutes, such
NLS_(computer_system)
Series of debugger programs
needed] DDT (Dynamic Debugging Technique), as implemented on the DECsystem-10 & DECSYSTEM-20 allowed references to symbols within the programming being debugged
Dynamic_Debugging_Technique
Organization
Network Solutions. On October 1, 1991, the NIC services were moved from a DECSYSTEM-20 machine at SRI to a Sun Microsystems SPARCserver running SunOS 4.1 at
InterNIC
Programming language
many home computers' rudimentary operating systems. Microsoft used its DECsystem-20 to produce assembly code for dozens of different computer systems and
Microsoft_BASIC
Type of computer instructions
IBM Corporation. August 1986. SA22-7125-2. Retrieved Sep 20, 2018. DECsystem-10 - DECSYSTEM--20 - Processor Reference Manual (PDF). Digital Equipment Corporation
Bit_manipulation_instructions
1982 video game
first wrote the game as DND, a 1976 version of Dungeons & Dragons for the DECsystem-10 mainframe computer. He continued to develop DND at Purdue University
Telengard
Operating system for DEC PDP-10
operating system from Digital Equipment Corporation (DEC) for the PDP-10 (or DECsystem-10) mainframe computer family. Launched in 1967, TOPS-10 evolved from
TOPS-10
Defunct international data communications network
on Digital Equipment Corporation's 36-bit hardware: the DECsystem-10 and also the DECSYSTEM-20, hence the 1022 name. 1022 was a hierarchical database system
Tymnet
1980. Initially available for Digital Equipment Corporation's DECsystem-10 and DECSYSTEM-20, a VAX version was released and installed January 1982. It was
Accent_R
DEC PDP-11, they subsequently began to support COBOL on DEC's DECsystem-10 & DECSYSTEM-20. VAX support came later. The specifications also permitted COBOL
Business_Controls_Corporation
Network protocol suite
August 19, 2018. Archived March 8, 2021, at the Wayback Machine "The DECSYSTEM-20 at Columbia University 1977-1988". Archived from the original on July
DECnet
OpenBSD 3.0, NetBSD 1.5.2. da Cruz, Frank; Gianone, Christine. "THE DECSYSTEM-20 AT COLUMBIA UNIVERSITY (1977-1988)". Columbia University, New York City
Columbia_MM
Software archive
White Sands Missile Range, arranged for the archive to be hosted on a DECSYSTEM-20 computer with ARPANET access, accessible via FTP at simtel20.arpa, later
Simtel
at research and academic sites PDP-6 Monitor ⇶ → TENEX ⇉ CP/M TOPS-20 DECsystem 20 1976-?? DEC Successor to TOPS-10 but more like TENEX TENEX→ TOPS-10→
Time-sharing_system_evolution
American computer scientist (1941–2006)
generations of the PDP-10, DECsystem-10 and DECSYSTEM-20. Bell, Thomas Hastings, Richard Hill and Kotok wrote that the DECSystem-10 accelerated the transition
Alan_Kotok
Computer instruction executing another instruction
Retrieved 20 June 2017. Holloway, J. (February 20, 1970). "Hardware Memo 2 - PDP-10 Paging Device" (PDF). MIT AI Lab. p. 11. DECsystem-10, DECSYSTEM-20 Processor
Execute_instruction
DEC high performance interface
"The DEC RP06 Disk Drive". columbia.edu. 1977. Retrieved 2024-06-09. DECSYSTEM-20 Site Preparation Guide. Digital Equipment Corporation. EK-DEC20-SP-002
Massbus
Defunct modem manufacturer
which they marketed as Control 10/20 (targeted at users of Digital Equipment Corporation's DECsystem-10 and DECSYSTEM-20). After trying their hand at time-sharing
Penril
operating system computing platforms, including Motorola 68000 series, DECSYSTEM-20s, Cray-1s, VAX, and many others. Today, PSL is mainly developed by
Portable_Standard_Lisp
Video game of multiple players
distributed to universities with DECsystem-10s. In 1981 Cliff Zimmerman wrote an homage to Star Trek in MACRO-10 for DECsystem-10s and -20s using VT100-series
Multiplayer_video_game
Series of discontinued Unix operating systems by DEC
workstations and DECsystem servers. Note that the DECstation and the later DECsystem products (as opposed to DEC's original DECsystem line) used MIPS processors
Ultrix
Software information file
Calif. at Berkeley on a CDC 6400. Except to convert the FORTRAN to the DECsystem-10 no changes have been made to the programs. For the test data SLIC and
README
General-purpose programming language
to $2,977 million in 2025). Digital Equipment Corporation maintained DECSYSTEM-10 Fortran IV (F40) for PDP-10 from 1967 to 1975. Compilers were also
Fortran
Discontinued family of computer operating systems
aspects of CP/M were influenced by the TOPS-10 operating system of the DECsystem-10 mainframe computer, which Kildall had used as a development environment
CP/M
1978 video game
Due in part to a fortuitous coincidence (MUD was written for the same DECSystem-10 computing platform that CompuServe used for its information service)
MUD1
Defunct computer museum in Seattle, Washington
PDP-10 KA10 (DECsystem-10) mainframe 1968 No No DEC PDP-10 KI10 (DECsystem-10) mainframe 1971 No No[citation needed] DEC PDP-10 KL10 (DECSYSTEM-2065) mainframe
Living Computers: Museum + Labs
Living_Computers:_Museum_+_Labs
Commands in some high-level programming languages
address. These commands originated with machine code monitors such as the DECsystem-10 monitor; these commands are particularly associated with the BASIC
PEEK_and_POKE
Computer bugs related to the year 2000
4 January 1975, overflowed the 12-bit field that had been used in the Decsystem 10 operating systems. There were numerous problems and crashes related
Year_2000_problem
Month of 1978
"Digital will be giving a product presentation of the newest members of the DECsystem-2020 family," inviting them to attend sessions on May 9 and May 11 at
May_1978
RISC microprocessor
Corporation (DEC) for their DECstation workstations and multiprocessor DECsystem servers. Evans & Sutherland for their Vision (ESV) series workstations
R3000
Line of computers sold by Digital Equipment Corporation
of RISC workstations and servers that ran Ultrix, the DECstation and DECsystem respectively, using processors from MIPS Computer Systems. In 1992 DEC
VAX
Data storage device
Archived from the original on April 15, 2005. Retrieved 2013-04-19. "DECsystem 5100 Maintenance Guide" (PDF). August 1990. Retrieved 2012-01-31. "3480
Tape_drive
Database utility on the ARPANET
total data stored was over 500 billion bits (62 GB) "Arpanet DBMS Uses Decsystem-10, Mass Memory". Computerworld. Vol. XI, no. 19. May 9, 1977. p. 30.
Datacomputer
Former American computer company
operating system had major similarities to the operating system of the DEC DECsystem-10. This may not be coincidental; legend has it that the founders based
Alpha_Microsystems
1976 video game
version were designed to run on the PDP-10 and used features unique to DECSYSTEMS-10 Fortran IV on that architecture, meaning that the program could not
Colossal_Cave_Adventure
Early object-oriented programming language
Norwegian Computing Center. Archived from the original on 2024-09-19. Retrieved 20 August 2025. Nygaard, Kristen (1978). "The Development of the Simula Languages"
Simula
Computer bus used on VAX computers
length of 25 metres (82 ft). DSSI support was later extended to MIPS-based DECsystems and DEC Alpha-based AlphaServer systems. DSSI peripherals could be distinguished
Digital Storage Systems Interconnect
Digital_Storage_Systems_Interconnect
DEC brand of computers
5000/200 models were stated as being able to run OSF/1, along with certain DECsystem models. User dissatisfaction with the decision, driven by uncertainty
DECstation
Interpreter that enables users to enter and run programs in the BASIC language
and the PEEK function (adapted from machine code monitors such as the DECsystem-10 monitor) provided direct memory access, for a variety of purposes,
BASIC_interpreter
Systems programming language used in the EMAS operating system
2004. "IMP11 User's Guide". Farvis, Keith M. (June 1978). "IMP on the DECsystem-10/20: Users Guide (Library Manual)". Stephens, Felicity; Murison, John.
Edinburgh_IMP
1978 video game
turns entering their commands. During a port to the PDP-10 (also called DECsystem-10), the game was more heavily modified and became DECWAR. The game was
Decwar
Computing standard based on MIPS architecture
opposed to compliant" with ACE in the form of various DECstation and DECsystem 5000 series models, in advance of a more comprehensive specification and
Advanced Computing Environment
Advanced_Computing_Environment
32-bit superminicomputer delivered in 1981 by Norsk Data
floating-point performance in server products, existing products such as the DECsystem 5400 could, for around £42,000 (or $57,534), offer comparable floating-point
ND-500
DECSYSTEM 20
DECSYSTEM 20
Surname or Lastname
English
English : from a variant of the medieval female personal name Mab(be), a short form of Middle English, Old French Amabel (from Latin amabilis ‘loveable’). This has survived into the 20th century in the short form Mabel.English : possibly from an unattested Old English male personal name, Mappa.English : from Old Welsh map, mab ‘son’, which was used as a distinguishing epithet.
Girl/Female
German
Mighty with a spear. Note: 'This Database is Copyright Muse Creations Inc. 2000'.
Girl/Female
Polish
Christian. Note: 'This Database is Copyright Muse Creations Inc. 2000'.
Girl/Female
Greek American
A , meaning famed. Famous bearer: 20th century British jazz singer Cleo Laine.
Girl/Female
Native American
Power of the moon Note: 'This Database is Copyright Muse Creations Inc. 2000'.
Surname or Lastname
English
English : variant of Lovell, derived from Anglo-Norman French lou ‘wolf’ + the diminutive suffix -el.Lowell is the surname of one of America’s most distinguished New England families, which have been prominent for over 200 years. Its founder, John Lowell (1743–1802), was a legislator and judge. The city of Lowell, MA was named in honor of his son Francis Cabot Lowell (1775–1817), a textile manufacturer.
Girl/Female
English
which is a . Note: 'This Database is Copyright Muse Creations Inc. 2000'.
Surname or Lastname
Swiss German
Swiss German : probably an altered form of Swiss Büchi. However, in The Mennonite Encyclopedia Bitsche (or Bitschi) is proposed as the origin. See also Beachy.English : variant of Peach.Swiss Surnames shows numerous Büchis (mainly in Zürich and Toggenburg) and several variants (Bücheli, Büchele, Bücheler, Büchler, etc.), whereas Bitsch(e) is listed four times and was apparently taken to Switzerland from Germany at the end of the 19th and beginning of the 20th centuries. Peachey is most common in Mifflin Co., PA; other variants appear in various communities.
Surname or Lastname
English, French, German, Dutch, Danish, and South Indian
English, French, German, Dutch, Danish, and South Indian : from the medieval personal name, of Biblical origin, from Aramaic t’Åm’a, a byname meaning ‘twin’. It was borne by one of the disciples of Christ, best known for his scepticism about Christ’s resurrection (John 20:24–29). The th- spelling is organic, the initial letter of the name in the Greek New Testament being a theta. The English pronunciation as t rather than th- is the result of French influence from an early date. In Britain the surname is widely distributed throughout the country, but especially common in Wales and Cornwall. The Ukrainian form is Choma.
Girl/Female
English
Adventurous. Note: This Database is Copyright 2000, Muse Creations Inc.
Boy/Male
English American Latin
Bald. Famous Bearers: Early 20th century American President Coolidge; fashion designer Calvin...
Surname or Lastname
English
English : from a pet form of the medieval female personal name Mab(be), a short form of Middle English or Old French Amabel (from Latin amabilis ‘lovable’). This has survived into the 20th century as a personal name in the short form Mabel.
Surname or Lastname
English (mainly southern England and South Wales) and Irish
English (mainly southern England and South Wales) and Irish : from the Old English personal name Hearding, originally a patronymic from Hard 1. The surname was first taken to Ireland in the 15th century, and more families of the name settled there 200 years later in Tipperary and surrounding counties.North German and Dutch : patronymic from a short form of any of the various Germanic compound personal names beginning with hard ‘hardy’, ‘brave’, ‘strong’.Warren Gamaliel Harding (1865–1923), the 29th president of the U.S., was born on a farm in OH, of English and Scottish stock on his father’s side. Early American bearers of this very common name include Joseph Harding who died at Plymouth in 1633. His great-great grandson Seth was a naval officer during the American Revolution.
Boy/Male
Spanish
Conqueror. Note: This Database is Copyright 2000, Muse Creations Inc.
Surname or Lastname
English and French
English and French : occupational name or habitational name for someone who was employed at or lived near one of the houses (‘temples’) maintained by the Knights Templar, a crusading order so named because they claimed to occupy in Jerusalem the site of the old temple (Middle English, Old French temple, Latin templum). The order was founded in 1118 and flourished for 200 years, but was suppressed as heretical in 1312.English : name given to foundlings baptized at the Temple Church, London, so called because it was originally built on land belonging to the Templars.Scottish : habitational name from the parish of Temple in Edinburgh, likewise named because it was the site of the local headquarters of the Knights Templar.
Surname or Lastname
Norwegian
Norwegian : habitational name from any of about 20 places so named for having a farmhouse with an upper story (see Loftus).English : variant of Loftus.
Boy/Male
Muslim
Group of camels that number from 100 to 200
Surname or Lastname
Northern Irish
Northern Irish : reduced form of Scottish McLean.English : perhaps a variant spelling of Lane.Finnish : ornamental name from laine ‘wave’. This is one of the most common names among those that were derived from words denoting natural features when hereditary surnames were adopted in Finland in the beginning of the 20th century. This name is found chiefly in southern Finland.French : metonymic occupational name for a worker or dealer in wool, from Old French la(i)ne ‘wool’ (Latin lana).
Girl/Female
Russian
crowned with laurels. Note: 'This Database is Copyright Muse Creations Inc. 2000'.
Girl/Female
German
Bright angel Note: 'This Database is Copyright Muse Creations Inc. 2000'.
DECSYSTEM 20
DECSYSTEM 20
Girl/Female
Indian
Being Stable
Boy/Male
Danish, German, Swedish
God is Gracious
Boy/Male
Finnish Latin
Boy/Male
Hindu
Boy/Male
Hindu, Indian
Very Heartly
Boy/Male
Hindu
Quite
Boy/Male
Arabic, Muslim, Sindhi
Better
Girl/Female
Afghan, Arabic, Australian, Muslim
Sagacious; Endowed with Insight; Wise; Female Version of Basir
Male
Hebrew
(×ֶפְרַיִ×) Variant spelling of Hebrew Ephrayim, EFRAYIM means "double-land; twin-land." In the bible, this is the name of the second son of Joseph.Â
Boy/Male
Hindu, Indian, Marathi
The Nectar of Flowers
DECSYSTEM 20
DECSYSTEM 20
DECSYSTEM 20
DECSYSTEM 20
DECSYSTEM 20
n.
A term used differently by different authorities; -- by some as equivalent to fricative, -- that is, as including all the continuous consonants, except the nasals m, n, ng; with the further exception, by others, of the liquids r, l, and the semivowels w, y; by others limited to f, v, th surd and sonant, and the sound of German ch, -- thus excluding the sibilants, as well as the nasals, liquids, and semivowels. See Guide to Pronunciation, // 197-208.
n.
A load; a heavy burden; hence, a certain weight or measure, generally estimated at 4,000 lbs., but varying for different articles and in different countries. In England, a last of codfish, white herrings, meal, or ashes, is twelve barrels; a last of corn, ten quarters, or eighty bushels, in some parts of England, twenty-one quarters; of gunpowder, twenty-four barrels, each containing 100 lbs; of red herrings, twenty cades, or 20,000; of hides, twelve dozen; of leather, twenty dickers; of pitch and tar, fourteen barrels; of wool, twelve sacks; of flax or feathers, 1,700 lbs.
n.
The fifth month of the French republican calendar adopted in 1793. It began January 20, and ended February 18. See Vendemiaire.
n.
The sixtieth part of a degree; sixty seconds (Marked thus ('); as, 10¡ 20').
n.
A small barrel of no certain dimensions. It may contain from 3 to 20 gallons, but it usually holds about 14/ gallons.
a.
Having a quality imparted by means of the nose; and specifically, made by lowering the soft palate, in some cases with closure of the oral passage, the voice thus issuing (wholly or partially) through the nose, as in the consonants m, n, ng (see Guide to Pronunciation, // 20, 208); characterized by resonance in the nasal passage; as, a nasal vowel; a nasal utterance.
n.
An Austrian silver coin equivalent to 20 kreutzers, or about 10 cents.
n.
A pantheistic eclectic school of philosophy, of which Plotinus was the chief (A. D. 205-270), and which sought to reconcile the Platonic and Aristotelian systems with Oriental theosophy. It tended to mysticism and theurgy, and was the last product of Greek philosophy.
n.
A rare metallic element of the aluminium group found in some minerals, as certain pyrites, and also in the lead-chamber deposit in the manufacture of sulphuric acid. It is isolated as a heavy, soft, bluish white metal, easily oxidized in moist air, but preserved by keeping under water. Symbol Tl. Atomic weight 203.7.
a.
Applied to, or distinguishing, a speech element consisting of tone, or proper vocal sound, not pure as in the vowels, but dimmed and otherwise modified by some kind of obstruction in the oral or the nasal passage, and in some cases with a mixture of breath sound; -- a term introduced by Dr. James Rush in 1833. See Guide to Pronunciation, //155, 199-202.
a.
The sixth month of the calendar adopted by the first French republic. It began February 19, and ended March 20. See Vend/miaire.
n.
A symbol representing twenty units, as 20, or xx.
n.
A former French money of account worth 20 sous, or a franc. It was thus called in distinction from the Paris livre, which contained 25 sous.
n.
The ninth month of the French Republican calendar, which dated from September 22, 1792. It began May, 20, and ended June 18. See Vendemiaire.
n.
A hymn, or other selection, sung during a church procession; as, the processional was the 202d hymn.
n.
One of the elements, a heavy, pliable, inelastic metal, having a bright, bluish color, but easily tarnished. It is both malleable and ductile, though with little tenacity, and is used for tubes, sheets, bullets, etc. Its specific gravity is 11.37. It is easily fusible, forms alloys with other metals, and is an ingredient of solder and type metal. Atomic weight, 206.4. Symbol Pb (L. Plumbum). It is chiefly obtained from the mineral galena, lead sulphide.
a.
Consisting of, or characterized by, voice, or tone produced in the larynx, which may be modified, either by resonance, as in the case of the vowels, or by obstructive action, as in certain consonants, such as v, l, etc., or by both, as in the nasals m, n, ng; sonant; intonated; voiced. See Voice, and Vowel, also Guide to Pronunciation, // 199-202.
n.
A French money of account, afterward a silver coin equal to 20 sous. It is not now in use, having been superseded by the franc.
n.
The Bull; the second in order of the twelve signs of the zodiac, which the sun enters about the 20th of April; -- marked thus [/] in almanacs.