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

The film even spawned a three-film franchise, with the entire trilogy eventually pulling in over one billion dollars in box office bucks. — Emily Maskell, IndieWire, 22 Oct. 2026

The WandaVision trilogy is coming to its conclusion later this month with VisionQuest, which premiered October 13 and will continue to air weekly until all eight episodes are dropped November 10. — Rosy Cordero, Deadline, 22 Oct. 2026

Damien Leone wrote and directed the trilogy, which stars David Howard Thornton as Art the Clown. — William Earl, Variety, 22 Oct. 2026

The Mass Effect trilogy, which began in 2007, married the wordy dialogue trees of role-playing games with run-and-gun gameplay, a formula that many other studios have attempted to copy, but few ever match its scale. — Washington Post, 21 Oct. 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