Noun

1. An opening in the crust of an astronomical body that emits steam and gases.

Quotations

• 2003: Masaya did not offer an opportunity to sample high-temperature fumaroles, but its neighbors, Momotombo and Cerro Negro volcanoes, are noted for their fumarolic activity — L.J. Wardell, P. Delmelle, T. Fischer, J.L. Lewicki, E. Malavassi, J. Stix, W. Strauch, Volcanic gas workshop features state-of-the-art measurement techniques.