Dictionary (n.) A rock composed of angular fragments either of the same mineral or of different minerals, etc., united by a cement, and commonly presenting a variety of colors.Thesaurus aa abyssal rock agglomerate agglomeration basalt bedrock block lava brash bunch clot cluster concrete concretion conglomerate conglomeration crag debris detritus druid stone festooned pahoehoe gneiss grain granite granule granulet gravel grit igneous rock lava limestone living rock magma mantlerock mass metamorphic rock monolith pahoehoe pillow lava porphyry pudding stone regolith rock ropy lava rubble rubblestone sand sandstone sarsen schist scoria scree sedimentary rock shelly pahoehoe shingle stone talus tufa tuff |