Origin: Greek suffix -logy
Trilogy has 2 different meanings across 1 category:
a set of three literary or dramatic works related in subject or theme
"The film trilogy explores the epic journey of a hero from his humble origins to ultimate victory."
A set of three works of art that are connected, and that can be seen either as a single work or as three individual works. They are commonly found in literature, film, or video games.
"The Lord of the Rings trilogy is celebrated for weaving together three distinct novels into one epic narrative about good versus evil."
In plain English: A trilogy is a set of three related stories, books, movies, or songs that are released together as part of one big series.
"The movie trilogy tells the story of a hero rising to power, facing great challenges, and finally achieving peace."
Usage: Use trilogy to describe any series of exactly three related creative works, such as films or novels, rather than using it for sets with different numbers of parts. This term applies whether the pieces function independently or form one continuous narrative arc.
The English word trilogy comes from the Latin term trilogia, which was adopted into English via learned borrowings rather than through everyday speech. It originally described a collection of three related works and is formed by combining the prefix for "three" with the suffix meaning "study or discourse."