Combination for a degree student with good average marks initially (7)
I believe the answer is:
amalgam
'combination' is the definition.
(I have seen 'combination of things' mean 'amalgam' so perhaps 'combination' could also mean 'amalgam')
'a degree student with good average marks initially' is the wordplay.
'degree student' becomes 'mal' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'with' says to put letters next to each other.
'initially' suggests taking the first letters.
The initial letters of 'good average marks' is 'gam'.
'a'+'mal'+'gam'='AMALGAM'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for amalgam that I've seen before include "Mixture - alloy of mercury" , "Mercury alloy - combination" , "often filling" , "Blend of diverse things" , "Mixture (for dental fillings)" .)