nick n.

1610s, "shallow recess in a wall," from French niche "recess (for a dog), kennel" (14c.), perhaps from Italian nicchia "niche, nook," which is said to be from nicchio "seashell," itself said by Klein, Barnhart, etc. to be probably from Latin mitulus "mussel," but the change of -m- to -n- is not explained (Century Dictionary compares napkin from Latin mappa). Watkins suggests that the word is from an Old French noun derived from nichier "to nestle, nest, build a nest," via Gallo-Roman *nidicare from Latin nidus "nest" (see nidus), but that, too, has difficulties. The figurative sense is recorded by 1725. Biological use dates from 1927.

masc. proper name, from French Nicolas, from Latin Nicholaus, Nicolaus, from Greek Nikholaos, literally "victory-people," from nikē "victory" (see Nike) + laos "people" (see lay (adj.)). The saint (died 326 C.E.) was a bishop of Myra in Lycia, patron of scholars, especially schoolboys. A popular given name in England in the Middle Ages (the native form, Nicol, was more common in early Middle English), as was the fem. form Nicolaa, corresponding to French Nicole. Colloquial Old Nick "the devil" is attested from 1640s, evidently from the proper name, but for no certain reason.