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

Or consider Jordan Strafer’s trilogy—Loophole (2023), Decadence (2024), and Talk Show (2026)—the last of which was shown in this year’s Whitney Biennial. — Eugenie Brinkema, ARTnews.com, 17 Oct. 2026

The trilogy’s conclusion, Culpa Nuestra (Our Fault), saw its trailer draw 163 million views in one week — the highest ever for an original streaming movie. — Rosy Cordero, Deadline, 16 Oct. 2026

In Cusk’s first novel after the blockbuster Outline trilogy, a woman invites an artist to stay at her home on a marsh, and things unravel from there. — Literary Hub, 15 Oct. 2026

In sum, The Godfather trilogy would be remembered even more favorably had there never been a third film. — Bobby Burack Outkick, FOXNews.com, 15 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