trilogy

noun

tril·​o·​gy ˈtri-lə-jē 

plural trilogies

: a series of three dramas or literary works or sometimes three musical compositions that are closely related and develop a single theme

Did you know?

Dozens of tragic trilogies were written for the Greek stage, though only one, Aeschylus's great Oresteia (consisting of Agamemnon, The Libation Bearers, *and *The Eumenides), has survived complete. Authors in later years have occasionally chosen to create trilogies to allow themselves to develop a highly complex story or cover a long span of time. Tolkien's Lord of the Rings wasn't actually intended as a trilogy, but since it was published in three volumes it's usually called one. George Lucas's three original Star Wars movies are an example of a film trilogy (which he followed many years later by another).

Examples of trilogy in a Sentence

the last book in the trilogy

Recent Examples on the Web

Meanwhile, in the co-main event, bantamweight champ Petr Yan, who is also in his second title reign, faces former titleholder Merab Dvalishvili in a trilogy bout. — Trent Reinsmith, Forbes.com, 18 Aug. 2026

The trilogy is the logical culmination of Cusk’s project up to that point. — Becca Rothfeld, New Yorker, 16 Aug. 2026

Seen together, the trilogy charts both a personal coming-of-age and a generational coming-to-grips with aging that, even when compared against similar serialized documentary experiments like Michael Apted’s 7 Up installments, feels wholly unique. — David Fear, Rolling Stone, 15 Aug. 2026

Gosling plays Kade Auberon, a Starfighter pilot (and possible mechanic), in the standalone film that will be set some time after the sequel trilogy. — Tracy Brown, Los Angeles Times, 15 Aug. 2026

Word History

Etymology

Greek trilogia, from tri- + -logia -logy

First Known Use

circa 1661, in the meaning defined above

Kids Definition

trilogy

noun

tril·​o·​gy ˈtril-ə-jē 

plural trilogies

: a series of three literary, dramatic, or musical works that are closely related and develop a single theme