treasure (n.)

1888, shortened from treasure trove (late 14c.), originally any precious metal object or cache of valuable objects one finds hidden whose owner is unknown. This is from Anglo-French tresor trové (late 12c.), translating Latin thesaurus inventus, literally "treasure found." As this usually meant ancient hoards, the term came to mean "treasure hoard" in popular use. The term also was rendered into English as treasure found from mid-15c.

French trove is past participle of trover "to find," from Old French trover, torver, a word of unknown origin, perhaps from Latin turbare "to move" (hence "to seek for") or a Medieval Latin *tropare "to compose, sing."

late 13c., tresourer, "warden of a hoard of valuables, person charged with protecting wealth or precious objects," from Old North French, Anglo-French tresorer, Old French tresorier, from tresor (see treasure (n.)). At first often an official in a city, church, household, etc.; mid-14c. as a high-ranking Crown official. The figurative sense of "one who or that which stores up" in any sense is from late 14c. 

Related: Treasurership. Fem. form tresouresse is attested from mid-15c. as "nun responsible for handling the financial affairs of her house;" John Davies (1590s) in "Orchestra" calls Memory "Wisdom's treasuress." A fem. form tresoriere (from Old French) "woman charged with keeping a treasure" is attested mid-14c. in a figurative sense (of maidenhood).