intransitive verb.
To be in a dormant or torpid state during a cold period, especially during the winter.
intransitive verb.
To be in an inactive or dormant state or period.
The Century Dictionary and Cyclopedia
To winter; pass the season of winter in close quarters or in seclusion, and generally in a torpid condition, as some animals.
Figuratively, to remain in seclusion; pass the time torpidly or apathetically.
the GNU version of the Collaborative International Dictionary of English
intransitive verb.
To winter; to pass the season of winter in close quarters, in a torpid or lethargic state, as certain mammals, reptiles, and insects.