Poetic shepherd, gracious fellow, embracing Yankee (7)
I believe the answer is:
corydon
'poetic shepherd' is the definition.
The definition suggests a singular noun which matches the answer.
'gracious fellow embracing yankee' is the wordplay.
'gracious' becomes 'cor' (both are exclamations of surprise).
'fellow' becomes 'don' (both can mean an academic).
'embracing' is an insertion indicator.
'yankee' becomes 'Y' (phonetic alphabet: alpha, bravo, charlie etc.).
'cor'+'don'='cordon'
'cordon' going around 'y' is 'CORYDON'.
Can you help me to learn more?
(Another definition for corydon that I've seen is " Rustic love".)