The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
bheid-
DEFINITION:
To split; with Germanic derivatives referring to biting (hence also to eating and to hunting) and woodworking. Derivatives include bite, bitter, and fission. 1a.beetle1, bite, from Old English btan, to bite; b.tsimmes, from Old High German bzan,bizzan, to bite. Both a and b from Germanic *btan.2. Zero-grade form *bhid-.a.bit2, from Old English bite, a bite, sting, from Germanic *bitiz;b. (i) bit1, from Old English bita, a piece bitten off, morsel; (ii) bitt, from a Germanic source akin to Old Norse biti, bit, crossbeam. Both (i) and (ii) from Germanic *bitn-;c. suffixed form *bhid-ro-.bitter, from Old English bit(t)er, “biting,” sharp, bitter. 3. O-grade form *bhoid-.a.bait1, from Old Norse beita (verb), to hunt with dogs, and beita (noun), pasture, food; b.abet, from Old French beter, to harass with dogs. Both a and b from Germanic *baitjan.4.bateau, boat; boatswain, from Old English bt, boat, from Germanic *bait-, a boat (< “dugout canoe” or “split planking”). 5. Nasalized zero-grade form *bhi-n-d-.–fid, fissi-, fissile, fission, fissure, vent2, from Latin findere, to split. (Pokorny bheid- 116.)
tan, to bite; b. tsimmes, from Old High German b
n-; c. suffixed form *bhid-ro-. bitter, from Old English bit(t)er, “biting,” sharp, bitter. 3. O-grade form *bhoid-. a. bait1, from Old Norse beita (verb), to hunt with dogs, and beita (noun), pasture, food; b. abet, from Old French beter, to harass with dogs. Both a and b from Germanic *baitjan. 4. bateau, boat; boatswain, from Old English b
t, boat, from Germanic *bait-, a boat (< “dugout canoe” or “split planking”). 5. Nasalized zero-grade form *bhi-n-d-. –fid, fissi-, fissile, fission, fissure, vent2, from Latin findere, to split. (Pokorny bheid- 116.) 
