a den or resting place of a wild animal

The cougar retired to its lair.

a secluded or hidden place, esp. a secret retreat or base of operations; a hideout or hideaway

a pirate's lair.

British . a place in which to lie or rest; a bed.

to place in a lair.

to serve as a lair for.

to go to, lie in, or have a lair.

noun

burrow , cave , den , earth , form , hideaway , hole , nest , pen , refuge , resting place , retreat , sanctuary , covert , cavern , habitat , haunt , hideout , shelter