In olden times hindustani classical music followed a strict form.
Raga had some stringent rules too.
The swara with which a Raag starts was called Grah Swara.
The most used Swara in a Raga was called Ansh Swara.
The swara with which a Raga ends is called Nyaas Swara of the Raga.
But nowadays, these swaras have lost their importance and are replaced by Vadi and Samvadi Swaras. Nowadays Ansh Swara is known as Vadi swara.
Further Reading: What are Swaras?