Leaves behind the bar for peers (12)
I believe the answer is:
counterparts
'leaves' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Maybe they are linked in a way I don't understand?
'behind the bar for peers' is the wordplay.
'behind' is a charade indicator (letters next to each other).
'the bar' becomes 'counter' (I've seen this before).
'for peers' becomes 'parts' (I can't justify this - if you can you should give a lot more credence to this answer).
'counter'+'parts' is 'COUNTERPARTS'.
Can you help me to learn more?
(Another definition for counterparts that I've seen is " Matches".)