Appalled at having broken? (9)
I believe the answer is:
shattered
'broken?' is the definition.
('shattered' can be similar in meaning to 'broken')
'appalled at' is the wordplay.
I cannot really see how this works, but
'at' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'having' acts as a link.
Can you help me to learn more?
(Other definitions for shattered that I've seen before include "Splintered" , "Broken into sharp pieces" , "Completely broken" , "devastated" , "bust" .)