IPA: /ˈnɪvəl/
KK: /ˈnɪvəl/
Relating to or occurring in snowy conditions or environments.
The nival zone of the mountain is covered in snow year-round.
Nival is derived from the Latin "nivalis" (meaning snowy), which is formed from "nix" (meaning snow) and the suffix "-alis" (meaning pertaining to). Thus, nival refers to something that is related to or characterized by snow.
Think of 'nix' meaning snow, and remember that 'nival' describes something that is snowy or related to snow.