1Of a policy: characterized by a contradictory or undefined position; ambiguous. Also occasionally of a politician: equivocating, non-committal. Now somewhat rare.
Originally with reference to the contradictory position held by the New South Wales Premier George Reid regarding referendums on a proposed Australian constitution in 1898.
2Also in form yes/no. Answerable by or definable in terms of a simple affirmation or negation.
Used as a non-committal or equivocating response or statement: perhaps; partly ‘yes’ and partly ‘no’.
In later use chiefly South African.
Late 19th century; earliest use found in Weekly Times (Melbourne). From yes + no.