Catnip

google

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late 18th century (originally US): from cat1 + nip, variant of dialect nep, nept, from medieval Latin nepta, from Latin nepeta ‘catmint’.

wiktionary

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Compound of cat +‎ Middle English nep, from Old English nepte, from Latin nepeta.

etymonline

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catnip (n.)

1712, American English, from cat (n.) + nip, from Old English nepte "catnip," from Latin nepta, name of an aromatic herb. The older name is Middle English catmint (mid-13c.). So called because cats are fond of it.