Trout dissected by teacher? (5)
I believe the answer is:
tutor
'teacher?' is the definition.
(I know that tutor is a type of teacher)
'trout dissected' is the wordplay.
'dissected' indicates anagramming the letters.
'trout' is an anagram of 'TUTOR'.
'by' acts as a link.
(Other definitions for tutor that I've seen before include "Trout (anag)" , "Private or university teacher" , "Personal teacher" , "Give individual instruction" , "Personal coach" .)