To enter a standby state which conserves power without losing the contents of memory
Your computer hibernates after it has been idle for the specified amount of time. — Microsoft Corp, Use Hibernate and Standby to Conserve Batteries (2001).
A deep sleep that can lasts for months that some animals take that reduces the amount of energy that they use When an animal is hibernating their heart beat slows down and they don't have to eat or go to the bathroom the whole time Polar bears don't quite hibernate, but they do sleep a lot
sleep during winter; "Bears must eat a lot of food before they hibernate in their caves"
{f} spend the winter in a dormant condition (of certain animals); spend the winter in a place with a milder climate (of people); retreat, be in seclusion, be inactive
Some animals go into a state of where they almost go to sleep for a long period and their bodies slow right down This allows them to survive the winter when there would be little food about
Animals that hibernate spend the winter in a state like a deep sleep. Dormice hibernate from October to May. if an animal hibernates, it sleeps for the whole winter (past participle of hibernare , from hibernus )