Disposition to show anger meant replacement (11)
I believe the answer is:
temperament
'disposition' is the definition.
('temperament' can be a synonym of 'disposition')
'anger meant replacement' is the wordplay.
'anger' becomes 'temper' (temper is a kind of anger**).
'replacement' indicates an anagram.
'meant' is an anagram of 'ament'.
'temper'+'ament'='TEMPERAMENT'
'to show' acts as a link.
(Other definitions for temperament that I've seen before include "Piano tuning; character" , "Person's nature; adjustment in piano tuning" , "Disposition; tuning adjustment" , "A person's nature as it affects behaviour" , "Frame of mind" .)