Point wrongly claimed (7)
I believe the answer is:
decimal
'point' is the definition.
(I have seen 'The point' mean 'decimal' so perhaps 'point' could also mean 'decimal')
'wrongly claimed' is the wordplay.
'wrongly' indicates anagramming the letters (I've seen this in other clues).
'claimed' anagrammed gives 'DECIMAL'.
(Other definitions for decimal that I've seen before include "of Number Ten" , "Medical (anag.)" , "Using powers of ten" , "System based on 10" , "A point in maths" .)