my arse!

my arse

An interjection denoting disbelief. Primarily heard in UK. Clean up the house, my arse! You've been promising to do that for months but haven't so much as lifted a finger around here. A: "John said he makes six figures a year." B: "My arse, he does. He's still living in that shabby flat."
See also: arse

my arse!

used to express strong contradiction or disbelief.
2005 Barbelith Underground Forums Opera my arse, it's a musical with a Napoleon complex. Though I still liked it.

My arse!

(British English, taboo, slang) used by some people to show they do not believe what somebody has said: An appointment at the dentist my arse! She’s gone shopping!