Replace exhaust with parts (4)
I believe the answer is:
swap
'replace' is the definition.
The answer and definition can be both to do with ownership as well as being verbs in their base form.
Maybe they are linked in a way I don't understand?
'exhaust with parts' is the wordplay.
'exhaust' becomes 'sap' (sapping is a kind of exhausting).
'with' becomes 'w' (abbreviation).
'parts' is an insertion indicator (in the sense of cuts or separates).
'sap' enclosing 'w' is 'SWAP'.
Can you help me to learn more?
(Other definitions for swap that I've seen before include "Exchange, substitute" , "Interchange" , "Switch" , "Exchange, barter" , "exchanged item" .)