Words related to *weid-
late 13c., auys "opinion," from Old French avis "opinion, view, judgment, idea" (13c.), from phrase ço m'est à vis "it seems to me," or from Vulgar Latin *mi est visum "in my view," ultimately from Latin visum, neuter past participle of videre "to see" (from PIE root *weid- "to see"). Meaning "opinion offered as worthy to be followed, counsel" is from late 14c.
The unetymological -d- (on model of Latin words in ad-) was inserted occasionally in French by scribes 14c.-16c. and was made regular in English 15c. by Caxton. Substitution of -c- for -s- is 18c., to preserve the breath sound and to distinguish from advise. Early Modern English tended to alternate -ce and -se endings in otherwise confusable noun-verb pairs, using -se for the verb and -ce for the noun: devise/device, peace/appease, practice/practise, license/licence, prophecy/prophesy.
"having psychic gifts, characterized by powers of clairvoyance," 1837, earlier "having insight" (1670s), from special use of French clairvoyant "clear-sighted, discerning, judicious" (13c.), from clair (see clear (adj.)) + voyant "seeing," present participle of voir, from Latin videre "to see" (from PIE root *weid- "to see"). Related: Clairvoyantly.
"one of the order of priests among the ancient Celts of Gaul, Britain, and Ireland," 1560s, from French druide (16c.), from Latin druis, fem. druias (plural druidae), from Gaulish Druides, from Celtic compound *dru-wid- "strong seer," from Old Celtic *derwos "true" (from PIE root *deru- "tree," especially oak) + *wid- "to know" (from PIE root *weid- "to see"). Hence, literally, perhaps, "they who know the oak" (perhaps in allusion to divination from mistletoe). Anglo-Saxon, too, used identical words to mean "tree" and "truth" (treow).
The English form comes via Latin, not immediately from Celtic. Old English had dry "magician," presumably from Old Irish drui. The Old Irish form was drui (dative and accusative druid; plural druad), yielding Modern Irish and Gaelic draoi, genitive druadh "magician, sorcerer." Not to be confused with the United Ancient Order of Druids, a secret benefit society founded in London 1781.
late 13c., from Old French envie "envy, jealousy, rivalry" (10c.), from Latin invidia "envy, jealousy" (source also of Spanish envidia, Portuguese inveja), from invidus "envious, having hatred or ill-will," from invidere "to envy, hate," earlier "look at (with malice), cast an evil eye upon," from in- "upon" (from PIE root *en "in") + videre "to see" (from PIE root *weid- "to see").
Jealousy is the malign feeling which is often had toward a rival, or possible rival, for the possession of that which we greatly desire, as in love or ambition. Envy is a similar feeling toward one, whether rival or not, who already possesses that which we greatly desire. Jealousy is enmity prompted by fear; envy is enmity prompted by covetousness. [Century Dictionary]
Similar formations in Avestan nipashnaka "envious," also "look at;" Old Church Slavonic zavideti "to envy," from videti "to see;" Lithuanian pavydėti "to envy," related to veizdėti "to see, to look at."
"plainly seen or perceived, manifest, obvious," late 14c., from Old French evident and directly from Latin evidentem (nominative evidens) "perceptible, clear, obvious, apparent" from ex "out, out of, fully" (see ex-) + videntem (nominative videns), present participle of videre "to see" (from PIE root *weid- "to see").