Sinatra perhaps is skilled practitioner (7)
I believe the answer is:
artisan
'skilled practitioner' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'sinatra perhaps' is the wordplay.
'perhaps' indicates anagramming the letters.
'sinatra' with letters rearranged gives 'ARTISAN'.
'is' is the link.
Can you help me to learn more?
(Other definitions for artisan that I've seen before include "crafty person?" , "man with skill" , "Skilled workman" , "Skilled worker at craft or trade" , "Skilled worker or craftsman" .)