The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
weid-
DEFINITION:
To see. Derivatives include guide, wisdom, kaleidoscope, Hades, unwitting, envy, idea, history, and penguin. I. Full-grade form *weid-.1a.twit, from Old English wtan, to reproach; b.guide, guidon, from Old Provençal guidar, to guide; c.guy1, from Old French guier, to guide; d.wite, from Old English wte, fine, penalty, from Germanic derivative noun *wti-.a–d all from Germanic *wtan, to look after, guard, ascribe to, reproach. 2. Suffixed form *weid-to-.a.wise1, from Old English ws, wise; b.wisdom, from Old English wsdm, learning, wisdom (-dm, abstract suffix; see dh-); c.wiseacre, from Old High German wzag, knowledgeable; d. (i)wise2, from Old English wse,ws, manner; (ii)guise, from Old French guise, manner. Both (i) and (ii) from Germanic *wssn-, appearance, form, manner. a–d all from Germanic *wssaz.3. Suffixed form *weid-es-.eidetic, eidolon, idol, idyll, –oid; idocrase, kaleidoscope, from Greek eidos, form, shape. II. Zero-grade form *wid-.1a.wit1, from Old English wit,witt, knowledge, intelligence; b.witenagemot, from Old English wita, wise man, councilor. Both a and b from Germanic *wit-.2.wit2, wot; unwitting, from Old English witan, to know, from Germanic *witan (Old English first and third person singular wt, from Germanic *wait, from Indo-European o-grade form *woid-). 3. Suffixed form *wid-to-.iwis, from Old English gewis,gewiss, certain, sure, from Germanic *(ga)wissa-, known (*ga-, past participial prefix; see kom-). 4. Form *wid-- (with the participial form *weid-to-). vide, view, visa, visage, vision, visit, visor, vista, voyeur; advice, advise, belvedere, black-a-vised, clairvoyant, envy, evident, improvise, interview, invidious, previse, provide, prudent, purvey, purview, review, revise, supervise, survey, from Latin vidre, to see, look. 5. Suffixed form *wid-es-y-.idea, ideo-, from Greek ide, appearance, form, idea. 6. Suffixed form *wid-tor-.history, story1; polyhistor, from Greek histr, wise, learned, learned man. 7.hadal, Hades, from Greek Haids (also Aids), the underworld, perhaps “the invisible” and from *wid-.8. Suffixed nasalized zero-grade form *wi-n-d-o-.a.colcannon, from Old Irish find, white (< “clearly visible”); b.penguin, from Welsh gwyn,gwynn, white. 9. Celtic *wid-, seer, in compound *dru-wid- (see deru-). III. Suffixed o-grade form *woid-o-.Veda; Rig-Veda, from Sanskrit veda, knowledge. (Pokorny 2. (e)di- (misprint for (e)id-) 1125.)
tan, to reproach; b. guide, guidon, from Old Provençal guidar, to guide; c. guy1, from Old French guier, to guide; d. wite, from Old English w
m, learning, wisdom (-d
-); c. wiseacre, from Old High German w
t, from Germanic *wait, from Indo-European o-grade form *woid-). 3. Suffixed form *wid-to-. iwis, from Old English gewis, gewiss, certain, sure, from Germanic *(ga)wissa-, known (*ga-, past participial prefix; see kom-). 4. Form *wid-
, knowledge. (Pokorny 2. 
(e)di- (misprint for 
