dower n.

c. 1400, "money, goods, or estate which a woman brings to her husband in marriage," from Anglo-French dowarie, Old French doaire (late 13c.) "dower, dowry, gift," from Medieval Latin dotarium, from Latin dotare "to endow, portion," from dos (genitive dotis) "marriage portion," from PIE *do-ti, from root *do- "to give." Compare dower.

dower, dowry. The two words, originally the same, are differentiated in ordinary literal use, dower being the widow's life share of her husband's property, & dowry the portion brought by a bride to her husband; but in poetic or other ornamental use dower has often the sense of dowry; & either is applied figuratively to talents &c. [Fowler]

*dō-, Proto-Indo-European root meaning "to give."

It forms all or part of: add; anecdote; antidote; betray; condone; dacha; dado; data; date (n.1) "time;" dative; deodand; die (n.); donation; donative; donor; Dorian; Dorothy; dose; dowager; dower; dowry; edition; endow; Eudora; fedora; Isidore; mandate; Pandora; pardon; perdition; Polydorus; render; rent (n.1) "payment for use of property;" sacerdotal; samizdat; surrender; Theodore; Theodosia; tradition; traitor; treason; vend.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit dadati "gives," danam "offering, present;" Old Persian dadatuv "let him give;" Greek didomi, didonai, "to give, offer," dōron "gift;" Latin dare "to give, grant, offer," donum "gift;" Armenian tam "to give;" Old Church Slavonic dati "give," dani "tribute;" Lithuanian duoti "to give," duonis "gift;" Old Irish dan "gift, endowment, talent," Welsh dawn "gift."