Regions in Far East (5)
I believe the answer is:
areas
'regions' is the definition.
(area is a kind of region)
'in far east' is the wordplay.
'in' says the answer is hidden in the clue.
'AREAS' is hidden within 'far east'.
(Other definitions for areas that I've seen before include "Localities" , "Geographical regions" , "Spaces covered by two-dimensional surfaces" , "Zones" , "Places" .)