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

With its third installment, her loose disco trilogy has finally run its course. —Harry Tafoya, Pitchfork, 20 Apr. 2026

Whereas the original book trilogy saw Tris choose Dauntless, the faction of bravery, in The Sixth Faction, tragedy strikes at her Choosing Ceremony, where her decision thrusts her into an underground rebellion. —Glenn Garner, Deadline, 19 Apr. 2026

The main characters of the Nuggets-Wolves trilogy are well defined – Jamal Murray, Nikola Jokic, Anthony Edwards, Rudy Gobert. —Jace Frederick, Twin Cities, 15 Apr. 2026

In addition to Han Solo, other original trilogy favorites are set to join the park on April 29, including Darth Vader, Luke Skywalker and Princess Leia. —William Earl, Variety, 15 Apr. 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