'Hornblende' definitions:

Definition of 'hornblende'

(from WordNet)
noun
A green to black mineral of the amphibole group; consists of silicates of calcium and sodium and magnesium and iron

Definition of 'Hornblende'

From: GCIDE
  • Hornblende \Horn"blende`\, n. [G., fr. horn horn + blende blende.] (Min.) The common black, or dark green or brown, variety of amphibole. (See Amphibole.) It belongs to the aluminous division of the species, and is also characterized by its containing considerable iron. Also used as a general term to include the whole species. [1913 Webster]
  • Hornblende schist (Geol.), a hornblende rock of schistose structure. [1913 Webster]