Sing, performing in C — ordinary (7)
I believe the answer is:
confess
'sing' is the definition.
The definition and answer can be both to do with communicating as well as being verbs in their base form.
Maybe there's an association between them I don't understand?
'performing in c ordinary' is the wordplay.
'performing' becomes 'on' (as in being on stage).
'in' is an insertion indicator.
'ordinary' becomes 'fess' (fess is a kind of ordinary).
'c'+'fess'='cfess'
'on' going inside 'cfess' is 'CONFESS'.
Can you help me to learn more?
(Other definitions for confess that I've seen before include "Concede" , "Admit (to wrongdoing)" , "Plead guilty (in order to receive absolution?)" , "Admit (to crime)" , "Tell a priest one's sins" .)