Marsh gas Meaning, Definition & Usage

  1. noun methane gas produced when vegetation decomposes in water

WordNet

Definitions
  1. . (Chem.) See under Gas.
Definitions
  1. (Chem.), a light, combustible, gaseous hydrocarbon, CH4, produced artificially by the dry distillation of many organic substances, and occurring as a natural product of decomposition in stagnant pools, whence its name. It is an abundant ingredient of ordinary illuminating gas, and is the first member of the paraffin series. Called also methane, and in coal mines, fire damp.

Webster 1913