The type of language used by all sides today (7)
I believe the answer is:
english
'the type of language' is the definition.
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for english that I've seen before include "The . . . . . . . Patient (film) (7)" , "Race" , "spin?" , "See 6" , "The Queen's language?" .)