Trachyte

1 definition found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Trachyte \Tra"chyte\, n. [Gr. ? rough, rugged: cg. F. trachyte.]
     (Geol.)
     An igneous rock, usually light gray in color and breaking
     with a rough surface. It consists chiefly of orthoclase
     feldspar with sometimes hornblende and mica.
     [1913 Webster]