Old-fashioned routine? (6,5)
I believe the answer is:
square dance
'old-fashioned routine?' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Maybe you can see an association between them that I can't see?
'old-fashioned routine?' is the wordplay.
'old fashioned' becomes 'square'.
'routine?' becomes 'dance' (I can't justify this - if you can you should give a lot more credence to this answer).
'square'+'dance'='SQUARE-DANCE'
Can you help me to learn more?
(Other definitions for square dance that I've seen before include "Entertainment for four couples" , "Series of steps with four couples" , "Activity for four couples" , "skipping diversion" , "US country fling with couples in formations(6.5)" .)