A huge fellow with no name turned up in forest (5)
I believe the answer is:
taiga
'forest' is the definition.
(type of forest)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for taiga that I've seen before include "Forested northern land" , "Russian forest area" , "Marshy pine forest" , "swampy forests" , "Northern region" .)