A phrase used in retort towards an individual (typically male), who is behaving or acting in an undesirable or unsavory manner towards or around user (1).

Can also in certain instances be used to point out certain individual's clumsiness (2).
(1)
Bartender: "Tony, your drunk, I'm gonna have to cut you off..."

Tony: "Well... You sir, are a FUCK"

(2)
Bobby, stumbling around unaware of his surroundings, accidentally knocks over and spills Tony's beer.

Tony angrily proclaims, pointing his finger in Bobby's face; "You sir, are a FUCK!"
by A Big Dumb Animal March 9, 2011
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