Definition of subnivean in English:
subnivean
adjective
Existing, living, or carried out underneath snow.
Origin
Mid 19th century; earliest use found in Sylvester Judd (1813–1853), novelist. From sub- + classical Latin niv-, nix snow + -ean.
Pronunciation
subnivean
/sʌbˈnɪvɪən/