LACCOLITH Meaning of LACCOLITH in English [ 'lakəlɪθ ]■ noun Geology a lens-shaped mass of igneous rock intruded between rock strata, causing doming.OriginC19: from Gk lakkos 'reservoir' + -lith . Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004