1 definition by OJSizzle

A person who feels It is a necessity to obtain or achieve everything despite its INSIGNIFICANT value. They feel the need to turn everything into a collection from Disney figurines to sexual encounters with peers.
Peer: I'll give you a twenty bag to suck my dicc out here in the hundred acre woods
Robbie: *Muffled gagging noises*
Pooh: Oh bother!

Piglet: He can't help it, he's a completionist.
by OJSizzle February 24, 2017
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