Question

who were untouchables

Answer 1

These are usually dalits.
They were called as untouchables.
These are those lower people or lower castes which were not touched by upper classes.

Answer 2

Answer:

Untouchable, also called Dalit, officially Scheduled Caste, in traditional Indian society, the former name for any member of a wide range of low-caste Hindu groups and any person outside the caste system.