What concert performers do their stuff in? (6)
I believe the answer is:
unison
This might be a double definition.
'what concert performers do' is the first definition.
The definition suggests a singular noun which matches the answer.
'stuff in?' is the second definition.
The answer and definition can be both human attributes as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'their' is the link.
Can you help me to learn more?
(Other definitions for unison that I've seen before include "Togetherness - TUC member" , "Complete agreement, harmony" , "In agreement - like sound of choir" , "All singing the same note" , "As one, singers perhaps" .)