The definition of a trilogy is a series of three complete books, films or creative works that are related in theme or sequence.(noun)
The series of three Matrix movies is an example of a trilogy.
See trilogy in Webster's New World College Dictionary
noun pl. trilogies
Origin: Gr trilogia: see tri- & -logy
See trilogy in American Heritage Dictionary 4
noun pl. tril·o·gies
Origin: Greek trilogiā, series of three related tragedies
Origin: : tri-, tri-
Origin: + logos, word, saying; see -logy.
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