South American rainforest (6)
I believe the answer is:
amazon
'south american rainforest' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for amazon that I've seen before include "Great river of S America, or a tough woman" , "Strong, well-built woman" , "Female warrior of Greek myth" , "Mythical woman warrior and river" , "big river" .)