Hate being unfairly tested (6)
I believe the answer is:
detest
'hate' is the definition.
(to detest is to hate or loathe)
'unfairly tested' is the wordplay.
'unfairly' indicates an anagram (I've seen this in other clues).
'tested' with letters rearranged gives 'DETEST'.
'being' acts as a link.
(Other definitions for detest that I've seen before include "Abominate" , "Despise or loathe" , "Hate a lot" , "Dislike heartily" , "Having a loathing" .)