half-arsed

Definition

Slang

  • adjective ill-considered, incomplete, ineffectual. An expression which appeared in British and American usage around the turn of the 20th century. The term may originate in the notion of something which has less than a whole solid base or, according to a more fanciful theory, derive from a jocular deformation of ‘haphazard’. In modern British speech it is sometimes used as a more vulgar version of half-hearted (its more probable inspiration).
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