Persian language spoken on a distant sea (5)
I believe the answer is:
farsi
'persian language' is the definition.
(I've seen this in another clue)
'on a distant sea' is the wordplay.
'on' means one lot of letters go next to another.
'a distant' becomes 'far' (I've seen this before).
'sea' becomes 'si' (I am not sure about this - if you are sure you should believe this answer much more).
'far'+'si' is 'FARSI'.
'spoken' acts as a link.
This may not be correct. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for farsi that I've seen before include "Iranian language, also widely spoken in Afghanistan" , "foreign language" , "Persian language" , "Modern Persian lang." , "Iran's official language" .)