Continent in Americas I assume (4)
I believe the answer is:
asia
'continent' is the definition.
(Asia is an example)
'in americas i assume' is the wordplay.
'in' says the answer is hidden in the clue.
'ASIA' is hidden within 'americas i assume'.
(Other definitions for asia that I've seen before include "Tigers found here" , "Continental land mass" , "lands in the east" , "Eastern continent" , "Great continent" .)