Grotto (6)
'grotto' is the definition.
(I know that cave is a type of grotto)
This is all the clue.
(Other definitions for cave that I've seen before include "Hollow in a cliff or underground" , "Natural hollow in side of hill or cliff" , "Natural underground chamber" , "Watch out" , "Beware" .)
'grotto' is the definition.
(I know that cavern is a type of grotto)
This is the entire clue.
(Other definitions for cavern that I've seen before include "Large cave" , "Large 24 chamber" , "Craven in a cave" , "Vast dark space" , "Grotto" .)