snake hibernation
Refers to the period when snakes enter their dens to hibernate, typically in winter. Used as a seasonal word in haiku and other traditional poetry.
'Snake hibernation' is a winter season word.
This haiku uses the phrase 'snake hibernation'.
Compound of 蛇 (へび, 'snake'), 穴 (あな, 'hole'), and に入る (にいる, 'to enter'). Literally 'snake enters its hole', referring to the hibernation behavior of snakes.