Pegmatite

2 definitions found

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

  Pegmatite \Peg"ma*tite\, n. [From Gr. ? something fastened
     together, in allusion to the quartz and feldspar in graphic
     granite: cf. F. pegmatite. See {Pegm}.] (Min.)
     (a) Graphic granite. See under {Granite}.
     (b) More generally, a coarse granite occurring as vein
         material in other rocks.


         [1913 Webster]

From WordNet (r) 2.0 [wn]:

  pegmatite
       n : a form of igneous rock consisting of extremely coarse
           granite resulting from the crystallization of magma rich
           in rare elements