adverb
slang, humorous, euphemistic North AmericanBackwards, back to front, the wrong way round; in a manner contrary to what is usual, expected, or logical.
adjective
slang, humorous, euphemistic North AmericanContrary to what is usual, expected, or logical; back-to-front, muddled, perverse.
Origin
Early 20th century. Humorous alteration of ass-backward (although this is first attested later).
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