biteyoudaoicibaDictYouDict[bite 词源字典]
bite: [OE] The Old English verb bītan came from prehistoric Germanic *bītan, which also produced German beissen and Dutch bijten. The short-vowel version of the base, *bit-, was the source of bit, beetle, and probably bitter, and is also represented in various non-Germanic forms, such as Latin fidere ‘split’ (from which English gets fission). Bait came via Old Norse from a causal usage, ‘cause to bite’, and passed via Old French into abet (the possible source of bet).
=> beetle, bit, bitter, fission[bite etymology, bite origin, 英语词源]
bite (v.)youdaoicibaDictYouDict
Old English bitan (class I strong verb; past tense bat, past participle biten), from Proto-Germanic *bitan (cognates: Old Saxon bitan, Old Norse and Old Frisian bita, Middle Dutch biten, Dutch bijten, German beissen, Gothic beitan "to bite"), from PIE root *bheid- "to split, crack" (see fissure).

To bite the bullet is said to be 1700s military slang, from old medical custom of having the patient bite a lead bullet during an operation to divert attention from pain and reduce screaming. Figurative use from 1891; the custom itself attested from 1840s. To bite (one's) tongue "refrain from speaking" is 1590s. To bite the dust "die" is 1750 (Latin had the same image; compare Virgil's procubuit moriens et humum semel ore momordit). To bite off more than one can chew (c. 1880) is U.S. slang, from plug tobacco.
bite (n.)youdaoicibaDictYouDict
c. 1200, from bite (v).