Rock band's joint (5)
I believe the answer is:
elbow
This clue might be a double definition.
'rock band's' is the first definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'joint' is the second definition.
(joint of the body)
Can you help me to learn more?
(Other definitions for elbow that I've seen before include "Hinged joint" , "sack?" , "Reject" , "Major arm joint" , "part of the body" .)