Anger returned about Heather (5)
I believe the answer is:
erica
'heather' is the definition.
(the plant genus Erica includes heather plants)
'anger returned about' is the wordplay.
'anger' becomes 'ire' (ire is intense rage).
'returned' says the letters should be written backwards.
'about' becomes 'ca' (abbreviation for circa).
'ire' in reverse letter order is 'eri'.
'eri'+'ca'='ERICA'
(Other definitions for erica that I've seen before include "found on the moors" , "Heather's Latin name?" , "Heathland shrub; girl's name" , "growing up on the moors" , "I care about Heather, oddly" .)