Allowed brief cut in learning (7)
I believe the answer is:
letters
'learning' is the definition.
(letters is a kind of learning)
'allowed brief cut' is the wordplay.
'allowed' becomes 'letted' ('let' can be a synonym of 'allow').
'brief' means to remove the last letter.
'cut' becomes 'rs' (I can't explain this - if you can you should believe this answer much more).
'letted' with its last letter taken away is 'lette'.
'lette'+'rs'='LETTERS'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for letters that I've seen before include "They may indicate a degree" , "landlords?" , "...as, for example" , "Characters" , "eg E G" .)