Origin: 1125–75; (noun) Middle English tresor < Old French < Latin thēsaurus storehouse, hoard (see thesaurus); (v.) Middle English, derivative of the noun
mid-12c., from O.Fr. tresor "treasury, treasure" (11c.), from Gallo-Romance *tresaurus, from L. thesaurus "treasury, treasure" (cf. Sp., It. tesoro), from Gk. thesauros "store, treasure, treasure house" (see thesaurus). Replaced O.E. goldhord. General sense of "anything