Unsettling, in a way (5)
I believe the answer is:
eerie
'unsettling in a way' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for eerie that I've seen before include "Oddly frightening" , "Spine-tingling" , "Sinister" , "Unnerving" , "spine-chilling" .)