(ˈθɪərəˌlaɪt) n (Geological Science) obsolete any type of igneous rock containing nepheline, plagioclase, augite, and olivine
theralite
theralite
[′ther·ə‚līt] (petrology) A dark-colored, visibly crystalline rock composed chiefly of pyroxene with smaller amounts of calcic plagioclase and nepheline.