umbrella term for people of South Asian descent. South Asian countries include Afghanistan, Bangladesh, Bhutan, Maldives, Nepal, India, Pakistan, and Sri Lanka.
As many countries and cultures are enveloped within this umbrella term, try to be as specific as possible. If you know or can ask someone if they are Nepalese, for example, that's better as it's more specific.
Do not assume someone is South Asian because of certain physical characteristics or language knowledge.
Additionally, these Asian subregions are important to differentiate as some regions were most fraught to imperialism and colonisation than others.