'firedamp' definitions:

Definition of 'firedamp'

From: WordNet
noun
A mixture of gases (mostly methane) that form in coal mines and become explosive when mixed with air

Definition of 'firedamp'

From: GCIDE
  • firedamp \firedamp\ n. a mixture of gases (mostly methane) that forms in coal mines and becomes explosive when mixed with air. It is a source of serious hazard in coal mining operations. [WordNet 1.5 +PJC]