Word Origin & History
slap1632, probably of imitative origin, similar to Low Ger. slappe, Ger. Schlappe. The noun is recorded from 1648; fig. meaning "insult" is attested from 1736. Slapdash (1679) is first attested in Dryden. Slap-happy (1936) originally meant "punch-drunk." Slapshot in ice hockey is recorded from 1942. Slap
on the wrist "very mild punishment" dates from 1914.