"Thesauri" is a word in ENGLISH

LaL Found. Thesaurus inventus, treasure-trove. Non est inventus, [he] is not found

A treasury or storehouse; hence, a repository, especially of knowledge; -- often applied to a comprehensive work, like a dictionary …

The treasury; a treasure. Thesaurus absconditus. In old English law. Treasure hidden or buried. Spelman. . Thesaurus inventus. In old …

Literally, treas-ure found. Money or coin, gold, silver, plate or bullion found hidden in the earth or oth-er private place, …

Hence, a book or work containing much valuable knowledge, wisdom, wit, or the like; a thesaurus; as, \" Maunder's Treasury …