Court under fire over being correct (5)
I believe the answer is:
exact
'being correct' is the definition.
('exact' can be similar in meaning to 'correct')
'court under fire over' is the wordplay.
'court' becomes 'ct'.
'under' means one lot of letters go next to another.
'fire' becomes 'axe' (I've seen this before**).
'over' says the letters should be written backwards.
'axe' written backwards gives 'exa'.
'ct' put after 'exa' is 'EXACT'.
(Other definitions for exact that I've seen before include "Spot-on" , "Correct; insist on" , "without rounding" , "Particular" , "Not approximate; inflict (revenge) on someone" .)