Can a Muslim from India or Pakistan define himself as "Hindu" even though he is not Hindu in terms of religion, based on the statement of a preacher that this description is geographical and includes anyone from the "Hindustan" region located in the Indus Valley?

The term "Hindu" originally referred geographically and ethnically to the inhabitants of the Indian subcontinent around the Indus River. It then evolved to include followers of Indian religions other than Islam. In the 18th century, Europeans used this term to distinguish them from Muslims ("Mohammedans"). By the mid-19th century, colonial texts differentiated them from Buddhists, Sikhs, and Jains. Today, the term is used exclusively for those who profess Hinduism. Therefore, it is impermissible for a Muslim to describe himself as "Hindu," as this implies professing Hinduism. However, if he intends to refer to geographical affiliation with India, he does not commit an act of disbelief by doing so.