Some nasty eye inflammation? (4)
I believe the answer is:
stye
'inflammation' is the definition.
(I've seen this before)
'some nasty eye' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'STYE' is hidden within 'nasty eye'.
(Other definitions for stye that I've seen before include "Eyelid infection" , "dump" , "It pains viewer" , "Eye problem" , "Inflammation on eyelid" .)