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n. pl. gab·bros
A usually coarse-grained igneous rock composed chiefly of pyroxene and calcic plagioclase feldspar. Also called norite.

[Italian, perhaps from Latin glaber, bald, beardless.]

gab·bro′ic (gă-brō′ĭk), gab′broid′ (găb′roid′) adj.


gabbro-like, esp of a rock in the petrographic clan which contains the gabbro family
References in periodicals archive ?
One of these, a medium-grained gabbroid, contains up to 3 cm long phenocrysts of plagioclase.
Unit G is composed of sparsely to moderately porphyritic basalt, with gabbroid xenoliths, plagioclase glomerocrysts and olivine microphenocrysts.
Pegmatoid and gabbroid layers in Jurassic Preakness and Hook Mountain basalts, Newark Basin, New Jersey.