Little boy's room? (3)

I believe the answer is:
den
This clue might be a double definition.
'little boy's' is the first definition.
'Den' can be an answer for 'boy's'. I am not certain of the 'little' bit.
'room' is the second definition.
(den is a kind of room)
Can you help me to learn more?
(Other definitions for den that I've seen before include "Animal habitation" , "Lair for animal or study for gent" , "Hideaway" , "Private office" , "Wild animal's lair" .)
