Pole on deck must leave university with top grade (4)
I believe the answer is:
mast
'pole on deck' is the definition.
'mast' can be an answer for 'pole' (mast is a kind of pole). I am not certain of the 'on deck' bit.
'must leave university with top grade' is the wordplay.
'leave' indicates named letters should be taken away.
'university' becomes 'U' (abbreviation as in UMass).
'with' indicates putting letters inside.
'top grade' becomes 'A' (top academic grade).
'must' with 'u' taken out is 'mst'.
'mst' going around 'a' is 'MAST'.
Can you help me to learn more?
(Other definitions for mast that I've seen before include "Main vertical spar of vessel" , "Long vertical pole" , "Spar to support a sail" , "Tall radio transmitter" , "nuts and seeds" .)