Language invented for international use (9)
I believe the answer is:
esperanto
'language invented for international use' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for esperanto that I've seen before include "Linguistic invention" , "Artificial international language devised in 1887" , "composite language" , "Personate in artificial language" , "Ape tenors (anag.)" .)