Big lie about the French being qualified (8)
I believe the answer is:
eligible
'being qualified' is the definition.
('eligible' can be similar in meaning to 'qualified')
'big lie about the french' is the wordplay.
'about' indicates anagramming the letters.
'the french' becomes 'le' ('the' in French).
'big'+'lie'='biglie'
'biglie' anagrammed gives 'eligib'.
'eligib'+'le'='ELIGIBLE'
(Other definitions for eligible that I've seen before include "Qualified or fit as bachelor may be" , "Qualified, entitled" , "Regarded as suitable, perhaps for marriage" , "Satisfying the appropriate conditions" , "Acceptable" .)