Geographically, it's in the form of a part of India! (4)
I believe the answer is:
asia
'india' is the definition.
The answer and definition can be both locations as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'geographically it's in the form of a part' is the wordplay.
I cannot really see how this works, but
'a' is present in the answer.
'part' could be 'si' (si is a kind of part) and 'si' is located in the answer.
A single letter 'a' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
'of' is the link.
Can you help me to learn more?
(Other definitions for asia that I've seen before include "Large area" , "Continent of the Hindu Kush" , "Major land mass" , "populous region" , "A great deal of land" .)