Bucket full of poor Tony's hair? (8)
I believe the answer is:
ponytail
'hair?' is the definition.
(ponytail is a kind of hair)
'bucket full of poor tony's' is the wordplay.
'bucket' becomes 'pail' ('pail' can be a synonym of 'bucket').
'full of' indicates putting letters inside.
'poor' indicates anagramming the letters.
'tony' is an anagram of 'onyt'.
'pail' enclosing 'onyt' is 'PONYTAIL'.
(Other definitions for ponytail that I've seen before include "hairdo" , "Drawn-back hair style" , "Plain toy (anag) - hairstyle" , "Arrangement of locks" , "Drawn-back hairstyle" .)