Pick up pound on merit (5)
I believe the answer is:
learn
'pick up' is the definition.
('learn' can be a synonym of 'pick up')
'pound on merit' is the wordplay.
'pound' becomes 'l'.
'on' means one lot of letters go next to another.
'merit' becomes 'earn' (I've seen this before).
'l'+'earn'='LEARN'
(Other definitions for learn that I've seen before include "Master" , "Succeed in school" , "Renal (anag)" , "Become aware of" , "Hear - memorise" .)