subnivean
sub-NIV-ee-un
Beneath the snow — the hidden winter world of tunnels, chambers, and runways that exists between the snowpack and the frozen ground. Lemmings, voles, and shrews live entire winters in the subnivean zone, insulated from the cold above, invisible to predators.
Etymology
Latin: sub (under) + niveus (snowy), from nix, nivis (snow).
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