Hates changing in a rush (5)
I believe the answer is:
haste
'a rush' is the definition.
('haste' can be a synonym of 'rush')
'hates changing' is the wordplay.
'changing' indicates an anagram.
'hates' anagrammed gives 'HASTE'.
'in' acts as a link.
(Other definitions for haste that I've seen before include "Urgency of action" , "Leader abandons modest" , "Excessive speed or urgency" , "Hurry, urgency" , "Hurriedness" .)