Relating to, composed of, or resembling diabase rock.
From diabase + -ic (adjective suffix meaning 'relating to'). Created in the 19th century for geological classification.
Adding -ic to rock names is how geologists quickly transform nouns into descriptions—diabasic allows scientists to describe entire landscapes without saying 'made of diabase' repeatedly.
Complete word intelligence in one call. Free tier — 50 lookups/day.