A forename of Sir Percy Blakeney (3)
I believe the answer is:
'a forename' is the definition.
Although both the answer and definition are singular nouns, I can't understand how they can define each other.
'sir percy blakeney' is the wordplay.
'KEN' is hidden within the letters.
However, I'm unsure how this is indicated.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for ken that I've seen before include "Identify; -- Livingstone" , "Know; man's name" , "Notice" , "Awareness" , "Understanding - boy's name" .)