When someone does or says something particularly stupid, one pretends to check for a fever as a gesture of false sympathy (or "cupping" their forehead). One then lifts their hand off their forehead and comes back down to smack them in the forehead. Cup 'n Smack is a form of tough love.
My best friend cup n' smacked me after I hooked up with my ex, again.

by the angel of your nightmares * December 9, 2008
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