Wherein the world is flat (5)
I believe the answer is:
atlas
'wherein the world is flat' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for atlas that I've seen before include "Segment of spine" , "Size of paper once" , "The first cervical vertebra" , "Titan who supported the heavens" , "travel book" .)