Meaning of diabase

di•a•base

Pronunciation: (dī'u-bās"), [key]
— n. Petrol.
  1. a fine-grained gabbro occurring as minor intrusions.
  2. a dark igneous rock consisting essentially of augite and feldspar; an altered dolerite.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.