- spunk (n.)
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- 1530s, "a spark," Scottish, from Gaelic spong "tinder, pith, sponge," from Latin spongia (see sponge (n.)). The sense of "courage, pluck, mettle" is first attested 1773. A similar sense evolution took place in cognate Irish sponnc "sponge, tinder, spark; courage, spunk." Vulgar slang sense of "seminal fluid" is recorded from c. 1888.