This document defines 55 key terms related to social inequality, including ascribed and achieved status, apartheid, blue collar/white collar workers, civil rights, discrimination, feminism, gendered division of labor, glass ceiling, Marxism, meritocracy, poverty, prejudice, privilege, racism, social mobility, stratification, and more. It provides brief definitions for each term to concisely explain concepts about social class, inequality, and related sociological topics.