noun an act of male masturbation, especially when performed by one sexual partner upon another. Shake 'n' Vac™ is a household cleaning product that achieved cult status as the result of a 1970s television commercial. During the all-singing and dancing demonstration, 'Do the Shake 'n' Vac / and put the freshness back' an attractive actress shook the tube-shaped packaging and white powder was scattered – the perfect metaphor UK, 2001