Harp player, perhaps, beginning to annoy girl (6)
I believe the answer is:
angela
'girl' is the definition.
'harp player perhaps beginning to annoy' is the wordplay.
'harp player perhaps' becomes 'angel' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'beginning to' says to take the initial letters.
The initial letter of 'annoy' is 'a'.
'angel'+'a'='ANGELA'
Can you help me to learn more?
(Other definitions for angela that I've seen before include "- Gheorghiu, Romanian soprano" , "girl" , ". . . Lansbury (actress)" , "------ Gheorghiu, diva" , "woman" .)