Liberal translation of writing system (7)
I believe the answer is:
braille
'writing system' is the definition.
(Braille is an example)
'liberal translation' is the wordplay.
'translation' indicates an anagram.
'liberal' is an anagram of 'BRAILLE'.
'of' acts as a link.
(Other definitions for braille that I've seen before include "type of relief" , "Liberal (anag) - reading system" , "Louis -------, inventor of an aid to the blind" , "French educationist" , "System of writing for the visually-impaired" .)