1 definition by Melman Mankiewicz

A person who feels It is a necessity to obtain or achieve everything despite its significant value. They feel the need to turn everything into a collection from sexual encounters with children to snuff films
Luke: Aidan why have you stolen all Zacs chromosomes he can't function without them
Aidan: I can't help it I'm a completionist
by Melman Mankiewicz February 22, 2016
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