"Do me a favor" means "no", with an attitude. Similar in meaning to the outdated phrase, "talk to the hand". When one person asks another person to do something undesirable, the response may be, "do me a favor". No specific favor is given, but the recipient is free to imagine one (go jump in the lake, etc.).
Wife: "Honey, can you take out the trash?"

Husband: "Do me a favor."
by Buck33wheat September 3, 2009
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An op word to tell another human being.Mostly known for making that person actually shut the fuck up.Also is very fun to say out loud.
kid:HHLUHU:FH:I :FHF:HF HF H: FH FH:UFH :UFHU: FH: A:FH !@#$%^&*()(*&^%$#@#$%^&*(F FH KLFLHFA:HH:FJVBDAKADOMG I LOVE FORTNITE AHHAHAHAHDPHFUHUFFHUYF*(T&Y*QR&($))*$)&!*$7$*!*_!$**)$*$!)*_$*$_$**$__*$($(&_*&()_*&)*(_*&**

You:do me a favor and shut the fuck up
by what is the point of living if December 2, 2020
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