mid-15c., in grammar, the case of nouns, pronouns, and adjectives denoting an indirect object of the action of the verb, from Latin dativus "pertaining to giving," from datus "given" (from PIE root *do- "to give"); in grammatical use from Greek dotikē (ptōsis) "dative (case)," from dotikos "of giving nature," from dotos "given" (from the same PIE root as the Latin word).
The notion is of the case that belongs to giving or commanding. Typically the case of the indirect object, but sometimes also denoting "motion toward." In old Germanic languages, the "fourth case," catch-all for Indo-European dative, ablative, locative, and other cases. In law, "that may be disposed of at pleasure," from 1530s.
*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."