chewyoudaoicibaDictYouDict[chew 词源字典]
chew: [OE] Chew, and its Germanic relatives German kauen and Dutch kauwen, can be traced back to a prehistoric West Germanic *kewwan. It has relatives in other Indo-European languages, including Latin gingīva ‘gum’ (source of English gingivitis).
=> gingivitis[chew etymology, chew origin, 英语词源]
chew (v.)youdaoicibaDictYouDict
Old English ceowan "to bite, gnaw, chew," from West Germanic *keuwwan (cognates: Middle Low German keuwen, Dutch kauwen, Old High German kiuwan, German kauen), from PIE root *gyeu- "to chew" (cognates: Old Church Slavonic živo "to chew," Lithuanian žiaunos "jaws," Persian javidan "to chew").

Figurative sense of "to think over" is from late 14c.; to chew the rag "discusss some matter" is from 1885, apparently originally British army slang. Related: Chewed; chewing. To chew (someone) out (1948) probably is military slang from World War II. Chewing gum is by 1843, American English, originally hardened secretions of the spruce tree.
chew (n.)youdaoicibaDictYouDict
c. 1200, "an act of chewing," from chew (v.). Meaning "wad of tobacco chewed at one time" is from 1725; as a kind of chewy candy, by 1906.