Definition - A figure of speech where emphasis is added by repeating a word.

Example -

(1) A rose is a rose is a rose. (Gertrude Stein)
(2) Words, words, words. (Hamlet)
(3) Location, location, location. (real estate agents)

Etymology -
The word derives from the Greek epi, upon + zeugnunai, to yoke (thus, a fastening upon).

Oxford English Dictionary -
Its first citation is from 1589:
"Ye have another sort of repetition, when … ye iterate one word without any intermission, as thus—
It was Maryne, Maryne, that wrought mine woe …
The Greekes call him, Epizeuxis, the Latins Subiunctio."
(Puttenham Eng. Poesie iii. xix. 167)

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