sima

English Thesaurus

1. rock that form the continuous lower layer of the earth's crust; rich in silicon and magnesium (noun.substance)

hypernym	:	rock, stone,
definition	:	material consisting of the aggregate of minerals like those making up the Earth's crust (noun.substance)

substance meronym	:	crust, earth's crust,
definition	:	the outer layer of the Earth (noun.object)