adj. — slang
drunk; intoxicated.
Half-cut is an informal synonym for drunk (see the 1991 quotation). Although definitions of half-cut appear to suggest various degrees of intoxication, from 'half-drunk' (see OED-3, s.v. "half" (1d)) to 'fairly drunk' (see COD-2, s.v. "half-cut"), Canadian attestations seem to use half-cut to indicate a serious state of inebriation (see the 1979 and 2002 quotations). Although the term has been labelled as Canadian as a result of the "British connection" (Barber 2008: 238) , it is used internationally, particularly in Australia, the UK and Ireland (see Chart 1). OED-3's earliest attestation of the term (see OED-3, s.v. "half" (1d)) antedates the earliest found Canadian attestation by over 75 years (see the 1965 quotation). The term could perhaps be considered Canadian in the North American context, where it has a lower frequency, yet this evidence strikes us as too weak to label this term Canadian.
See also COD-2, s.v. "half-cut", which is marked "Cdn& Brit.".
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Chart 1: Internet Domain Search, 17 Jul. 2014