Talk that may come naturally (3)
I believe the answer is:
gas
'talk' is the definition.
(thesaurus)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for gas that I've seen before include "Chat (colloq.)" , "could be embarrassing for American" , "Something that is neither solid not liquid" , "Domestic fuel" , "Fumes, vapour" .)