Complaint following group of footballers' language (5)
I believe the answer is:
farsi
'language' is the definition.
(I know that Farsi is a natural language)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for farsi that I've seen before include "Iran's official language" , "Language of Iran" , "Modern Persian lang." , "foreign language" , "Persian language" .)