Pronunciation: (mō-fet'; Fr. mô-fet'), [key]
1. a noxious emanation, consisting chiefly of carbon dioxide, escaping from the earth in regions of nearly extinct volcanic activity.
2. one of the openings or fissures from which this emanation issues. Also,mof•fette'.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.