TANTALITE Meaning of TANTALITE in English [ 'tantəlʌɪt ]■ noun a rare, dense black mineral consisting of a mixed oxide of iron and tantalum, of which it is the principal source.OriginC19: from tantalum + -ite 1 . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004