bottomland (n.)
- basin
- bog
- bottom
- bottoms
- campo
- champaign
- delta
- desert
- down
- downs
- fell
- fen
- fenland
- flat
- flats
- glade
- grassland
- heath
- holm
- level
- llano
- lowland
- lowlands
- mare
- marsh
- marshland
- meadow
- mere
- mesa
- mire
- moor
- moorland
- morass
- moss
- mud
- pampas
- peneplain
- plain
- plains
- plateau
- prairie
- quagmire
- quicksand
- savanna
- slough
- steppe
- sump
- swale
- swamp
- swampland
- table
- tableland
- tundra
- upland
- vega
- veld
- wallow
- wash
- weald
- wold