Extent of anger varies (5)
I believe the answer is:
range
'extent' is the definition.
(I know that range is a type of extent)
'anger varies' is the wordplay.
'varies' indicates an anagram.
'anger' anagrammed gives 'RANGE'.
'of' acts as a link.
(Other definitions for range that I've seen before include "Area for shooting practice" , "where cattle may graze" , "Scope - cowboys' home" , "Limits - scope" , "Kitchen gadget" .)