Proto-Indo-European Roots

Root/Stem: *dó-
Meanings:  to give, to take, exchange
Hellenic Greek didómi (I give) 
New Greek dido (I give)



Latin dare (to give), (I give), dedi (I gave); donum (a gift, a talent), Oscan deded (he gave), didest (he will give), donom (a gift), Umbrian dirsa- (I give), Pelignan dida- (I give); > 
Daco-Romanian da (to give), Megleno-Romanian dare, Istroromanian dou (I give), Spanish dar, Catalan donar, Italian dare, Ladin der, Romanian a da, French donner, Aromanian dau, Sardinian dare, Portuguese dar, Occitan douna
Celtic Common Celtic *dó- (to give); > 
Old Irish dobiur, tabur (to give), tabraim (I give thou), Irish & Scottish Gaelic tabhair (give!), 
Irish dán (fate, destiny), Welsh dawn (a gift, talent)
Indic Sanskrit dá- (to give), dadáti (he gives); 
Gypsy dav (to give), Lahnda dewen, Nepali dinu, Kashmiri dyunu, Singhalese denawa, Khaskura dinu, Punjabi & Hindi & Urdu dena, Bengali deoa, Marathi dene
Dardic Khowar dom (I give), doy (he will give)
Iranian Avestan dadáiti (he gives), > 
Ossetic daettyn (to give), Baluchi datha, Tadjik dodan, Persian dadan
Anatolian Common Anatolian *da- (to give, to take); > 
Hittite da- (to give), Luwian da- (to take), Lydian da (to give), dét (property)
Armenian tam (I will give), dal, tal (to give), turkh (a gift)
Venetic doto 'given';
Albanian dhashë (gave)
Baltic Lithuanian duoti (to give), duodu (I give), Old Prussian dátweí (to give, to let), padátan (given), Sudovian dátun (to give), dais (give!), Latvian dot (to give)
Slavic Common Slavic *dati (to give), *damï (I give, I will give); > 
Ukrainian & Old Church Slavonic & Slovene & Czech & Serbian dati (to give), Bulgarian & Macedonian dam (I give), Belorussian dats' (to give), Polish & Upper Sorbian dac', Lower Sorbian das', Russian dat' (to give), davat' (to give many times), daju (I give), dam (I will give)
Notes: It is strange to see how the same stem can mean opposite verbs, "to give" and "to take". But it seems that in Proto-Indo-European this stem denoted something connected with the exchange, where both sides participate. This was discovered, when Luwian and Hittite texts opened the meaning "to take", though the majority of Indo-European languages agree to "to give". 
The verb was athematic in ancient IE tongues, such as Greek and Sanskrit, and was conjugated with the ending *-mi in the 1st person singular in the present. Interesting that the stem was reduplicated practically in all branches of the family: this "double stem" was a rather frequent phenomenon in Indo-European.