trilogy

[tril-uh-jee] /ˈtrɪl ə dʒi/
noun, plural trilogies.
1.
a series or group of three plays, novels, operas, etc., that, although individually complete, are closely related in theme, sequence, or the like.
2.
(in ancient Greek drama) a series of three complete and usually related tragedies performed at the festival of Dionysus and forming a tetralogy with the satyr play.
3.
a group of three related things.
Origin
1655-65; < Greek trilogía. See tri-, -logy
Examples from the web for trilogy
  • Nor, according to the third of this convenient trilogy of papers, is a sense of fairness rooted in culture.
  • Most major action set pieces from the trilogy have been re-created in the game.
  • The first of a promised trilogy from a master of fiction.
  • But the second trilogy certainly had a built-in audience.
  • Well, that too is alive in the form of a commissioned single-volume abridgment of my trilogy.
  • Call it a trilogy, smack a number on it, pump out the books at the rate of one a year.
  • Subsequent volumes in the series were sequels to the original trilogy or filled in its gaps.
  • As a result, the lyrics of the trilogy were about hopelessness.
British Dictionary definitions for trilogy

trilogy

/ˈtrɪlədʒɪ/
noun (pl) -gies
1.
a series of three related works, esp in literature, etc
2.
(in ancient Greece) a series of three tragedies performed together at the Dionysian festivals
Word Origin
C19: from Greek trilogia; see tri-, -logy
Word Origin and History for trilogy
n.

"any series of three related works," 1660s, from Greek trilogia "series of three related tragedies performed at Athens at the festival of Dionysus," from tri- "three" (see three) + logos "story" (see logos).

trilogy in Technology
language
A strongly typed logic programming language with numerical constraint-solving over the natural numbers, developed by Paul Voda at UBC in 1988. Trilogy is syntactically a blend of Prolog, Lisp, and Pascal. It contains three types of clauses: predicates (backtracking but no assignable variables), procedures (if-then-else but no backtracking; assignable variables), and subroutines (like procedures, but with input and system calls; callable only from top level or from other subroutines).
Development of Trilogy I stopped in 1991. Trilogy II, developed by Paul Voda 1988-92, was a declarative general purpose programming language, used for teaching and to write CL.
(https://fmph.uniba.sk/~voda).
["The Constraint Language Trilogy: Semantics and Computations", P. Voda, Complete Logic Systems, 741 Blueridge Ave, North Vancouver BC, V7R 2J5].
(2000-04-08)
Encyclopedia Article for trilogy

a series of three dramas or literary or musical compositions that, although each is in one sense complete, have a close mutual relation and form one theme or develop aspects of one basic concept. The term originally referred specifically to a group of three tragedies written by one author for competition. This trilogy constituted the traditional set of plays presented in Athens by a number of competitors at the 5th-century-BC drama festivals known as the Great Dionysia. One of the first authors to present such a trilogy was Aeschylus, whose Oresteia is the only surviving example from that time. Modern examples of trilogies include Robertson Davies's Deptford Trilogy and Roddy Doyle's Barrytown Trilogy.

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