Son to pick up clipping (5)
I believe the answer is:
shear
'clipping' is the definition.
'son to pick up' is the wordplay.
'son' becomes 's'.
'to pick up' becomes 'hear' (hearing is a kind of picking up).
's'+'hear'='SHEAR'
(Other definitions for shear that I've seen before include "Cut with clippers" , "Fleece; cut" , "Barber" , "Cutter" , "Cut wool off (a sheep)" .)