1. For a place where animals live:
* घोंसला (ghonsla): This word literally means "nest," but can also be used for a den where animals live.
* मांद (mand): This is a more general word for a den or lair, especially for wild animals.
2. For a cozy room in a house:
* आरामगृह (aaramgriha): This word means "rest house" and can be used for a cozy room in a house, like a den.
* बैठक (baithak): This word means "sitting room" and is often used for a den where people gather.
3. For a secret hideout:
* छिपने का स्थान (chhipne ka sthan): This literally means "place to hide" and can be used for a secret den.
* गुफा (gufa): This word means "cave" and can be used for a secret hideout or den.
The best word to use will depend on the context. If you can provide more information about what kind of den you are referring to, I can give you a more accurate translation.