Lurk (5)
'lurk' is the definition.
(synonyms)
This is all the clue.
(Other definitions for skulk that I've seen before include "Move secretly" , "Lie in wait" , "Lurk or loiter stealthily" .)
'lurk' is the definition.
(prowling is a kind of lurking)
This is the entire clue.
(Other definitions for prowl that I've seen before include "Hunt" , "Steal around predatorily" , "Walk menacingly" , "Walk around predatorily" , "Slink after prey" .)