Turn wife on part of foot (5)
I believe the answer is:
wheel
'turn' is the definition.
(I've seen this before)
'wife on part of foot' is the wordplay.
'wife' becomes 'w' (abbreviation).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'part of foot' becomes 'heel' (heel is a part of the foot).
'w'+'heel'='WHEEL'
(Other definitions for wheel that I've seen before include "Cycle; swivel" , "Turn on axis" , "Circular frame on axle" , "Circular frame with spokes" , "Fly in a wide circle" .)