Hates changing in a rush (5)
I believe the answer is:
haste
'a rush' is the definition.
(I know that rush can be written as haste)
'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" .)