Definitions for "Peridotite"
An eruptive rock characterized by the presence of chrysolite (peridot). It also usually contains pyroxene, enstatite, chromite, etc. It is often altered to serpentine.
an ultrabasic (extremely low SiO2) igneous rock, consisting almost entirely of olivine. Approximate composition of the upper mantle.
A granular igneous rock composed essentially of olivine with some form of pyroxene or hornblende. Biotite and chromite are the chief accessory minerals.