Spare place finally accepted by officer not attached to body (14)
I believe the answer is:
extracorporeal
'not attached to body' is the definition.
(extracorporeal means outside the body)
'spare place finally accepted by officer' is the wordplay.
I cannot quite see how this works, but
'spare' could be 'extra' (synonyms) and 'extra' is present in the answer.
'accepted' could be 'a' (financial abbreviation) and 'a' is found in the answer.
'officer' could be 'co' (Commanding Officer abbreviation) and 'co' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
(Another definition for extracorporeal that I've seen is " Occurring outside the body".)