English
groundmass
From ground + mass.
Proto-Indo-European *gʰrem- ‘floor, settlement’
Proto-Germanic *grunduz ‘ground, foundation’
Proto-West Germanic *grundu
Old English grund
Middle English ground
English ground
Ancient Greek μᾶζα ‘barley-cake, lump of dough’
Latin massa ‘lump, dough’
Anglo-Norman masse
Middle English masse ‘lump, quantity of matter’
English mass
Today it means
noun The matrix of fine-grained crystalline material in which larger crystals are embedded.
Language periods are conventional ranges, not dates for this word.
Etymograph / groundmass