marsh gas

noun
1.
a gaseous decomposition product of organic matter, consisting primarily of methane.
Also called swamp gas.
Origin
1775-85, Americanism
Examples from the web for marsh gas
  • Well, a crowd gathered round and a scientist said it was marsh gas.
  • Also called marsh gas, methane is a colorless, odorless gas.
  • We always thought it was marsh gas or phosphorus but some believed that the lights were spirits or fairies, good or bad.
British Dictionary definitions for marsh gas

marsh gas

noun
1.
a hydrocarbon gas largely composed of methane formed when organic material decays in the absence of air
marsh gas in Medicine

marsh gas n.
See methane.