Slap
来自Big Physics
late Middle English (as a verb): probably imitative. The noun dates from the mid 17th century.
wiktionary
From Middle English slappen, of uncertain origin, possibly imitative. Compare Low German Slappe(“slap”), whence also German Schlappe(“defeat”).
etymonline
slap (v.)
late 15c., "strike with the open hand," from slap (n.). As an adverb, 1670s, "suddenly;" 1829, "directly." Related: Slapped; slapping.
slap (n.)
mid-15c., probably of imitative origin, similar to Low German slappe, German Schlappe. Figurative meaning "insult, reprimand" is attested from 1736. Slap-happy (1936) originally meant "punch-drunk." Slap on the wrist "very mild punishment" dates from 1914.
