Meaning of pneumatolysis

pneu•ma•tol•y•sis

Pronunciation: (n"mu-tol'u-sis, ny"-), [key]
— n. Geol.
  1. the process by which rocks are altered or minerals and ores are formed by the action of vapors given off by magma.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.