Advanced Braille letters (7)
I believe the answer is:
liberal
'advanced' is the definition.
(thesaurus)
'braille letters' is the wordplay.
'letters' indicates anagramming the letters.
'braille' anagrammed gives 'LIBERAL'.
(Other definitions for liberal that I've seen before include "Large-minded" , "Ample; former politician" , "Broad-minded in Braille" , "Tolerant and open-minded in Braille" , "Bountiful" .)