Noun. An act of masturbation, perhaps implying one done at a particularly opportunist moment. A spoonerism on crafty wank. See 'wank'. E.g."I know she was sexy, but having a wafty crank under the table is disgusting."
WAFTY CRANK
Meaning of WAFTY CRANK in English
Slang English vocab. Английский сленговый словарь. 2012