Character of eg hairdo quietly altered (9)
I believe the answer is:
ideograph
'character' is the definition.
(I know that ideograph is a type of character)
'eg hairdo quietly altered' is the wordplay.
'quietly' becomes 'p' (musical symbol).
'altered' indicates an anagram.
'eg'+'hairdo'+'p'='eghairdop'
'eghairdop' with letters rearranged gives 'IDEOGRAPH'.
'of' is the link.
(Other definitions for ideograph that I've seen before include "symbol" , "sort of character!" .)