Show annoyance with a troublesome blister? (7)
I believe the answer is:
bristle
'show annoyance with' is the definition.
(I've seen this before)
'a troublesome blister?' is the wordplay.
'a troublesome' indicates an anagram.
'blister' is an anagram of 'BRISTLE'.
(Other definitions for bristle that I've seen before include "Stand up" , "React in an offended way" , "Look angry" , "A stiff hair on chin" , "Stiff fibre" .)