Exasperating (7)
I believe the answer is:
irksome
'exasperating' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for irksome that I've seen before include "Smokier (anag.)" , "Bothersome, annoying" , "Tiresome, irritating" , "Burdensome and tedious" , "bugging" .)