Question

why do we call Indian plateau as a Peninsular plateau define peninsula​

Answer 1

a peninsula is apiece of land surrounded by water on three sides

Answer 2

Peninsula is a geographic term which means a land mass covered by water on three sides. Like Indian plateau. On its east, there is Bay of Bengal, on the west it has Arabian Sea and on the south it has Indian Ocean. However, it has huge Gangetic plain on its north. Hence, it qualifies the definition of peninsula where from it has derived its name - The great Indian peninsula.