1 definition by Derfilicious

verb: to do something stupid, immature. to lack rational judgment.

noun: the space underneath a man's scrotum before his anus; a normal person minus reason and accountability.
I can't believe I stapled my scrotum to my chair again. I really pulled a derf.

Dude, you only worked 3 hours today, don't pull a derf.
by Derfilicious December 16, 2007
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