School yet to deal with inflammation (4)
I believe the answer is:
stye
'inflammation' is the definition.
(I've seen this before)
'school yet to deal with' is the wordplay.
'school' becomes 's' ().
'to deal with' indicates an anagram (to deal with can mean to tidy up or sort out).
'yet' with letters rearranged gives 'tye'.
's'+'tye'='STYE'
(Other definitions for stye that I've seen before include "Eyelid sore" , "Eye blemish" , "Seeing problem" , "Eye complaint" , "Ocular affliction" .)