nicotinic (adj.)

also nicotin, poisonous volatile alkaloid base found in tobacco leaves, 1819, from French nicotine, earlier nicotiane, from Modern Latin Nicotiana, the formal botanical name for the tobacco plant, named for Jean Nicot (c. 1530-1600), French ambassador to Portugal, who sent tobacco seeds and powdered leaves from Lisbon to France 1561. His name is a diminutive of Nicolas (see Nicholas).

Middle English -ik, -ick, word-forming element making adjectives, "having to do with, having the nature of, being, made of, caused by, similar to," from French -ique and directly from Latin -icus or from cognate Greek -ikos "in the manner of; pertaining to." From PIE adjective suffix *-(i)ko, which also yielded Slavic -isku, adjectival suffix indicating origin, the source of the -sky (Russian -skii) in many surnames. In chemistry, indicating a higher valence than names in -ous (first in benzoic, 1791).

In Middle English and after often spelled -ick, -ike, -ique. Variant forms in -ick (critick, ethick) were common in early Modern English and survived in English dictionaries into early 19c. This spelling was supported by Johnson but opposed by Webster, who prevailed.