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

Teller first rose to fame with his role in the Divergent film trilogy, but gained critical acclaim for his role in Whiplash, which earned him various award nominations. —Kelsie Gibson, PEOPLE, 25 Apr. 2026

The panel, moderated by June Kim, ranged across the decade-plus collaboration between Chen, Yann Yann and their lead actor Koh Jia Ler, who was cast at age 11 through a 10-month search beginning with 8,000 children, rediscovered on Instagram at 17, and now appears in the trilogy’s final film at 25. —Naman Ramachandran, Variety, 25 Apr. 2026

Her trilogy of war novels—Machine Dreams (Vietnam), Lark and Termite (the Korean War), a finalist for the National Book Critics Circle fiction award and the Pulitzer Prize award-winning Night Watch (the Civil War)—solidified her place as a literary icon. —Literary Hub, 21 Apr. 2026

Created by Graham Yost based on Hugh Howey’s New York Times bestselling trilogy , Season 3 continues the saga of a dystopian society of 10,000 people living underground under mysterious circumstances, while revealing an origin story set centuries earlier. —Denise Petski, Deadline, 21 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