"large carnivorous or omnivorous mammal of the familyUrsidae," Old Englishbera "a bear," from Proto-Germanic*bero, literally "the brown (one)" (source also of Old Norsebjörn, Middle Dutchbere, Dutchbeer, Old High Germanbero, GermanBär), usually said to be from PIE root*bher- (2) "bright; brown." There was perhaps a PIE*bheros "dark animal" (comparebeaver (n.1) and Greekphrynos "toad," literally "the brown animal").

Greekarktos and Latinursus retain the PIE root word for "bear" (*rtko; seearctic), but it is believed to have been ritually replaced in the northern branches because of hunters' taboo on names of wild animals (compare the Irish equivalent "the good calf," Welsh "honey-pig," Lithuanian "the licker," Russianmedved "honey-eater"). Others connect the Germanic word with Latinferus "wild," as if it meant "the wild animal (par excellence) of the northern woods."

Used of rude, gruff, uncouth men since 1570s. Symbolic of Russia since 1794. The stock market meaning "speculator for a fall" is by 1709, a shortening ofbearskin jobber (from the proverbsell the bearskin before one has caught the bear); i.e. "one who sells stock for future delivery, expecting that meanwhile prices will fall." Paired withbull from c. 1720.Bear claw as a type of large pastry is from 1942, originally chiefly western U.S.Bear-garden (1590s) was a place where bears were kept for the amusement of spectators.

late 14c., "a beaver," from Old Frenchcastor (13c.), from Latincastor "beaver," from Greekkastor "beaver," perhaps literally "he who excels," and thus identical with the name of one of the divine twins (with Pollux), worshipped by women in ancient Greece as a healer and preserver from disease (seeCastor).

It has been assumed that the hero's name was given to the animal because he was a noted healer and the odorous reddish-brown secretions of the inguinal sacs of the animal (Latincastoreum), were used medicinally in ancient times, especially for women's diseases. But the animal did not live in Greece in classical times (the closest beavers were north of the Black Sea), and the name probably was borrowed from another language, perhaps influenced by the hero's name. The Greek word replaced the native Latin word for "beaver" (fiber).

In English,castor is attested in the secretion sense from late 14c. Moderncastor oil is so-called by 1746; it is made from seeds of the plantRicinus communis but supposedly possesses the laxative qualities (and taste) of beaver juice.