also: カスト
noun
caste
Refers to the hereditary social classes of the Indian subcontinent, or metaphorically to rigid social hierarchies.
from Portuguese casta
インドのカースト制度は複雑だ。
India's caste system is complex.
あの会社には見えないカーストがある。
There is an invisible caste-like hierarchy in that company.
Standard katakana spelling from Portuguese 'casta'.
Rarely used kana form; カースト is overwhelmingly more common.
階級 is a general term for class or rank in any society, while カースト specifically evokes the Indian caste system or a similarly rigid, birth-based hierarchy.
Borrowed from Portuguese 'casta', originally meaning 'race' or 'lineage', and used in the context of the Indian caste system.