Latin American plain (5)
I believe the answer is:
llano
'latin american plain' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for llano that I've seen before include "(South American) grassy plain" , "Flat area" , "Grassy plain in South?America" , "Treeless area" , "Treeless grassy plain in South America" .)