Shoe with a lip (5)
I believe the answer is:
wedge
'shoe' is the definition.
(I know that wedge is a type of high-heeled shoe)
'with a lip' is the wordplay.
'with' becomes 'w' (abbreviation).
'a lip' becomes 'edge' (I've seen this before).
'w'+'edge'='WEDGE'
(Other definitions for wedge that I've seen before include "It may cause division" , "Tapered block" , "Force (into narrow space); type of golf club" , "Device eg to keep door open" , "Lofting golf club" .)