Using the definition from Wikipedia
Hibernation is a state of inactivity and metabolic depression in endotherms. Hibernation refers to a season of heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It most commonly occurs during winter months.
More colloquially expressed, it's a state some animals enter to save energy (usually during winter) by sleeping more or less the whole time or at least being at rest more than usually.
The verb "hibernate" means to spend time in hibernation. Not all languages can express this in a single word. E.g. in German one would say "Winterschlaf halten".
How would "to hibernate" be expressed in Esperanto?
Would it be "vintre dormi" or something like that? If so, how would one distinguish from just normal "sleeping in Winter" unrelated to hibernation, like in "I don't sleep well in winter, because by bedroom is always either too cold or too warm."?
Google translate suggests "hiberni", but I don't quite trust that, as I couldn't find it in any Esperanto dictionary.