Troglodyte's home (4)
I believe the answer is:
cave
'troglodyte's home' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for cave that I've seen before include "Hollow - warning" , "Warning - grotto" , "Underground enclosure with surface access" , "Hollow in a rock" , "Primitive dwelling" .)