Learn what's in the area (4)
I believe the answer is:
hear
'learn' is the definition.
(I know that learn can be written as hear)
'in the area' is the wordplay.
'in' says the answer is hidden in the clue.
'HEAR' is hidden in the letters of 'the area'.
'what's' acts as a link.
(Other definitions for hear that I've seen before include "Find out" , "receive information" , "Try (in court)" , "to judge" , "Pay attention" .)