late 14c., "pertaining to the animal spirit of man," that is, "pertaining to the merely sentient (as distinguished from the intellectual, rational, or spiritual) qualities of a human being," from Latin animalis, from animale (see animal (n.)).
From 1540s as "pertaining to sensation;" 1630s as "pertaining to or derived from beasts;" 1640s as "pertaining to the animal kingdom" (as opposed to vegetable or mineral); 1650s as "having life, living." Animal rights is attested from 1879; animal liberation from 1973. Animal magnetism originally (1784) referred to mesmerism.