per·ma·frost 
(pûrmə-frôst′, -frŏst′)
(pûrmə-frôst′, -frŏst′)n.
Permanently frozen subsoil, occurring throughout the Polar Regions and locally in perennially frigid areas.
[PERMA(NENT) + FROST.]
- indisposition
- indisputability
- indisputable
- indisputableness
- indisputably
- indissolubility
- indissoluble
- indissolubleness
- indissolubly
- indistinct
- indistinctive
- indistinctively
- indistinctly
- indistinctness
- indistinguishability
- indistinguishable
- indistinguishableness
- indistinguishably
- indite
- inditement
- inditer
- indium
- individual
- individualism
- individualist