caste

This term carries a heavy weight of social rigidity and predetermined destiny. It describes a system where an individual's place in the hierarchy is fixed from birth, creating a sense of permanence and inevitability that differs from the fluid nature of social class. In modern usage, the word is often employed to describe any closed social group that excludes outsiders, even in non-religious or non-traditional settings. It implies a sharp, impermeable boundary between the insiders and those deemed inferior or excluded.