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dar (Verb) "to give"
12th cent. From Latin dare 'id.' From Proto-Italic *dide- 'id.' From Proto-Indo-European *di̯-deh3- "to be giving." Reduplication of *deh3- "to give" to form the imperfective aspect.
Indo-European
Romance
Asturian dar, Portuguese dar, Galician dar, Catalan dar, Italian dare, Aromanian dau, dari Romanian da, dare, Sardinian dare
Italic
Oscan didet "will give," Umbrian teřa "gives," Paelignian datas "given," Venetic doto "gave," Vestian didet "gives," Pre-Samnite tetet "gave," Marsian ded "given"
Celtic
Old Irish do-rata "giveable"
Albanian
Albanian (archaic) dhae
Balto-Slavic
Old Church Slavonic dati, Lithuanian dúoti
Hellenic
Ancient Greek δίδωμι (dídomi)
Armenian
Armenian tam
Indo-Iranian
Sanskrit dádāti, Young Avestan daδāiti

For the origin of irregular form doy "I am," see -oy.

The root *deh3- meant both give and take at once, and the root probably ment "to stretch out one's hand" in Pre-Proto-Indo-European. As one linguist wrote on this root: "The root *dō- means “give” in all Indo-European languages. However, there is one language which fails to conform to this definition: in Hittite, dā- means “take” and pai- ‘give’... The notion of “give” and “take” are thus linked in prehistoric Indo-European." ~ E. Benveniste, Indo-European Language and Society (1973)