Surly person in college upset lawyers (4)
I believe the answer is:
crab
'surly person' is the definition.
(I've seen this in another clue)
'college upset lawyers' is the wordplay.
'college' becomes 'c'.
'upset' says the letters should be written backwards.
'lawyers' becomes 'bar' (the bar can mean the legal profession).
'bar' written backwards gives 'rab'.
'c'+'rab'='CRAB'
'in' is the link.
(Other definitions for crab that I've seen before include "Clawed shellfish" , "move obliquely" , "Seashore crustacean" , "Seashore creature" , "Decapod crustacean" .)