Abbreviated DYFWMD, this is a phrase commonly used in place of "don't mess with me", but with a more traditional meaning of "leave my penis alone".

This saying is thought to have been originated by Duke Wellington III, after a fellow nobleman who was stricken by the Black Plague, would use his decaying hand to taunt and otherwise pester the Duke. While this was primarily in jest, after the nobleman threatened to grab Wellington's scrotum (in effect, making it fall off), Wellington fatefully proclaimed "DONT YOU FUCK WITH MY DICK!" -- then proceeded to unsheathe his rapier and chop off the nobleman's infected hand.

True to it origins, this phrase is commonly followed by an act of aggression or violence.
Masculine Form - Contemporary

Dude 1: "Hey, I'm drinking your last beer…
Dude 2: "DONT YOU FUCK WITH MY DICK!" (punches Dude 1 in the head)

Masculine Form - Traditional

Dude 1: "Give me the remote or I’ll punch you in the balls.”
Dude 2: "DONT YOU FUCK WITH MY DICK!" (punches Dude 1 in the head)

Feminine Form

Girl 1: "Damn, that's your boyfriend...he's sexy! Does he like blondes?"
Girl 2: "DONT YOU FUCK WITH MY DICK!" (punches Girl 1 in the vagina)
by munkman September 18, 2011
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