I adopt a Latin form of language (7)
I believe the answer is:
italian
'language' is the definition.
(I know that Italian is a type of Latinian language)
'i adopt a' is the wordplay.
'adopt' becomes 'tali' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'a' becomes 'an'.
'i'+'tali'+'an'='ITALIAN'
'latin form of' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for italian that I've seen before include "being in Europe" , "Nationality of benito or Giuseppe" , "Nationality of citizen of Capri" , "Nationality of native of Calabria" , "'From Milan or Venice, say (7)'" .)