virgin snow; untracked snow
Refers to fresh, untouched snow with no footprints or tracks. Often used in skiing, mountaineering, or poetic contexts.
スキー場でまだ誰も滑っていない処女雪を見つけた。
I found virgin snow at the ski resort that no one had skied on yet.
朝の山道は処女雪で真っ白だった。
The mountain path in the morning was pure white with untracked snow.
Compound of 処女 (virgin) and 雪 (snow), literally 'virgin snow'. The exact historical derivation is uncertain, but the term is conventionally associated with the idea of untouched, pristine snow.