Wife moves very slowly in heels (6)
I believe the answer is:
wedges
'heels' is the definition.
(wedge is a kind of heel)
'wife moves very slowly' is the wordplay.
'wife' becomes 'w' (abbreviation).
'moves very slowly' becomes 'edges' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'w'+'edges'='WEDGES'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for wedges that I've seen before include "Shoves in between other objects, packs tightly" , "They taper from a thick to a thin end" , "Golf irons with weighted heads and angled faces" , "They taper to a thin edge" , "Chunks" .)