swamp gasnoun [ C usually singular ]
uk/ˈswɒmp ˌɡæs/us/ˈswɑːmp ˌɡæs/a gas produced in a swamp by decaying plants that are covered by water:
You could smell the swamp gas a mile off.
Thesaurus: synonyms and related words
Geography: wetland
- bog
- boggy
- fen
- floodplain
- marsh
- marshland
- marshy
- mire
- morass
- peat bog
- quagmire
- quicksand
- slough
- swamp
- swampland
- swampy
- water meadow
- waterlogged
- wetland