nurse (n.1)

c. 1200, norice, nurrice, "wet-nurse, woman who nourishes or suckles an infant; foster-mother to a young child," from Old French norrice "foster-mother, wet-nurse, nanny" (source of proper name Norris), from Late Latin *nutricia "nurse, governess, tutoress," noun use of fem. of Latin nutricius "that suckles, nourishes," from nutrix (genitive nutricis) "wet-nurse," from nutrire "to suckle" (see nourish).

The modern form of the English word is from late 14c. By 16c. also "female servant who has care of a child or children" (technically a dry-nurse). As "one who protects or that which nurtures, trains, or cherishes," from early 15c. Meaning "person (usually a woman) who takes care of sick or infirm persons" in English is recorded by 1580s.

"dogfish, shark," a name given to various sharks of inactive habits, c. 1500, of unknown origin. Perhaps identical to nurse (n.1), but the sense is obscure, or perhaps a different word conformed to it by folk-etymology.

1530s, "to suckle (an infant), nourish at the breast;" 1520s in the passive sense, "to bring up" (a child); alteration of Middle English nurshen, norishen "to supply with food and drink, feed; bring up, nurture" (c. 1300; see nourish), in part by influence of nurse (n.1).  From 1540s as "promote growth or vigor in, encourage." Sense of "tend to in sickness or infirmity" is recorded by 1736. Related: Nursed; nursing.