Summarise shortly (5)
I believe the answer is:
recap
'summarise' is the definition.
(I've seen this before)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for recap that I've seen before include "Repeat of main points" , "Restate" , "Summarise briefly (abbr)" , "Run through again (Inf)" , "Sum up (abbrev.)" .)