the.com/caste

means A rigid social category you're born into, which largely determines your status, occupations, and who you may marry, regardless of what you later achieve.

from From Portuguese 'casta' meaning 'race' or 'lineage,' itself from Latin 'castus' meaning 'pure' or 'chaste' — the idea being a lineage kept unmixed. Portuguese traders and colonizers in India applied this word to the complex Hindu social system of varna and jati they encountered, and 'caste' stuck in English from there. So the word's root is really about purity and not mixing bloodlines — a fittingly unsettling origin for a system about birth deciding your worth.