In a way it repays harshness (8)
I believe the answer is:
asperity
'harshness' is the definition.
(thesaurus)
'in a way it repays' is the wordplay.
'in a way' indicates an anagram.
'it'+'repays'='itrepays'
'itrepays' is an anagram of 'ASPERITY'.
(Other definitions for asperity that I've seen before include "Harshness or severity of manner" , "Harshness of tone or manner" , "Roughness of temper" , "'Sharpness, harshness (8)'" , "Harshness, bitter coldness" .)