While writing text in Hindi/Sanskrit (Devanagari script), I need a quick way to insert the Avagraha symbol(). It turns out there is an undocumented shortcut on the Mac Hindi QWERTY keyboard for that and that is \ in Hindi Transliteration keyboard.

Alternatively, there is option + shift + . in Hindi - InScript keyboard.

Oh, and don’t forget to enable Caps Lock for quick switching between the English and a non-English (In my case, Devanagari) keyboard.

Mac OS language settings