Two-dimensional sphere? (4)

I believe the answer is:

area

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'sphere?' is the definition.
('area' can be a synonym of 'sphere')

I don't understand how the rest of the clue works.

(Other definitions for area that I've seen before include "Region; extent of a surface" , "Field of activity or surface" , "Extent of a 2-dimensional surface" , "Speaking formally to (someone)" , "Succession, order" .)

I've seen this clue in the Evening Standard.

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