Proto-Indo-European Roots

Proto-Indo-European Roots

Root/Stem:	*weid-

Meaning:	to know, to see

Cognates:	Greek *oida* (I know); *idein* (to see): w disappears everywhere in Ionic and Attic dialects; Doric Greek woida* (I know)
Italic	Latin *videó* (I see); > Sardinian *videre* (to see), Aromunian *vedu, Romanian vedea, Ladin vair, Italian vedere, Catalan veurer, Spanish & Portuguese ver, Occitan veire, French voir*
Celtic	Common Celtic wid- (to know), widtos (knowledge); windo- (white, clearly seen) > Old Irish fís* (vision), *find* (white), *fiuss* (knowledge)*, ro-fhetar* (I know); Welsh *gwyn* (white), Gaulish *vindos* (white), Breton *gwenn* (white), Cornish *guyn* (white), Irish & Scottish Gaelic *fios* (knowledge), *fís* (vision), *fionn* (white)
Iranian	Avestan *vaeda* (I know), *vaédha* (knowledge, information), *vista* (known)
Indic	Sanskrit *véda* (I know) - from here the name Veda comes
Balkan	Phrygian *wit-* (to know), *witeto* (he looked)
Armenian	Armenian *gitem* (I know)
Germanic	Common Germanic wit- (to know); > Gothic & Old Swedish & Old English witan* (to know), Old Norse *vita, Old High German wizzan, Old Frankish wita; Gothic weitan* (to see); English *wise, German wissen* (to know), Icelandic & Faroese *vita, Norwegian vite, Swedish veta, Danish vide, Frisian witten, Dutch weten, Afrikaans weet*
Baltic	Common Baltic woid- (to know), wid- (to see); > Old Prussian *waidimai* (we know), *widdai* (I saw); Lithuanian *vysti* (to see), Sudovian *izvíst* (to see), *vidét* (see; borrowed from Slavic)
Slavic	Common Slavic vide.ti (to see), ve.dati (to know); > Ukrainian *viditi, vidati,* Bulgarian *vidya* (I see), Macedonian *vidam* (I see), Serbo-Croatian *vidjeti* (to see), Slovene & Czech *videti* (to know), *vedeti* (to know), Slovak *videt'* (to see), *vedet'* (to know), Polish *widziec'* (to see), *wiedziec'* (to know), Lower Sorbian *wjez'es'* (to know), *widz'es'* (to see), Belorussian *vedac'* (to know), Russian *videt'* (to see), *vest'* (news), Old Russian *vedat'* (to know)

Notes:	Different grades of ablaut generated different meanings of the same root. In several languages the word for 'to know' acts as a Perfect tense form (like Greek *oida*). The explanation seems simple: 'I know' meant just 'I have seen'.