A gorilla is dangerous (5)
I believe the answer is:
hairy
This clue is a double definition.
'a gorilla is' is the first definition.
(I know this)
'dangerous' is the second definition.
(I've seen this before)
(Other definitions for hairy that I've seen before include "Having had a close shave? Not so" , "Perilous" , "alarming" , "Armpits can be" , "Scary" .)