Dear Kaushik,

A linguistic minority is the group of people whose mother tongue is different from that of the majority in that state or part of that state. The constitution provides security for the protection of the interest of linguistic minorities.

According to Article 29 of the Indian Constitution:-

 "any section of the citizens residing in any part of India having a distinct language, script or culture of its own, shall have the right to conserve the same"

According to the Supreme court, the definition for a linguistic minority is:-

"a minority either linguistic or religious is determinable only by reference to the demography of the State and not by taking into consideration the population of the country as a whole"

Hope this helps.

Thank You.