Tutor in pain during most of term (7)
I believe the answer is:
teacher
'tutor' is the definition.
(I've seen this before)
'pain during most of term' is the wordplay.
'pain' becomes 'ache' (ache is a kind of pain**).
'during' means one lot of letters goes inside another.
'most of' means to remove the last letter.
'term' with its last letter taken away is 'ter'.
'ache' put into 'ter' is 'TEACHER'.
'in' acts as a link.
(Other definitions for teacher that I've seen before include "'Instructor, educator (7)'" , "Schoolmaster" , "Chips, perhaps?" , "The trainer" , "One who might give lines" .)