assbackwards

or ass·back·ward

[ as-bak-werdz ]

adverb

, Slang: Sometimes Vulgar.

1. in an order or way reverse from the usual:

   You've sewn the sleeve on assbackwards.

2. in a manner incongruously or preposterously counter to what is customary, probable, or feasible:

   The plan fell apart because everything leading up to it was handled assbackwards.

Word History and Origins

Origin of assbackwards¹

First recorded in 1935–40; ass ² + backwards