DCHP-1 Online
permafrost [< permanent + frost] 
n. See 1957 quote.
See also: dry permafrost perma-ice
- 1742 (1852) [The frost is never out of the ground; how deep, we cannot be certain.]
- 1946 Permafrost . . . is a pressing geologic problem, for most of the North is characterized by it.
- 1957 This enemy has been with us always, but only in 1943 was given an English name: permafrost. The Russians call it vechnaia merzlota, or "perennially frozen ground."
- 1966 "Left-over ice pushed up by the spring break-up," explained Capt. Brinkie, "sitting on the permafrost; it'll stay there 'til freeze-up."
- 1742 (1852) [The frost is never out of the ground; how deep, we cannot be certain.]