Behind the word 'integrate' lies a striking Latin metaphor: wholeness as the state of being untouched. Latin integer meant 'complete' or 'whole,' built from in- (not) and the root of tangere (to touch) — something integer was something from which nothing had been removed. The verb integrare (to make whole, to restore) entered English in the 1630s, arriving simultaneously in mathematics and general usage. In calculus, integration assembles infinitely small pieces into a complete whole; in everyday language, it means combining separate parts into a unified entity. The social sense — ending racial segregation by combining previously separated communities — became the word's most charged meaning during the American civil rights movement of the 1950s and 1960s. The Brown v. Board of Education ruling in 1954 made 'integration' a household word. The family tree from tangere is extensive: 'tangible' (touchable), 'tangent' (touching a curve), 'contact' (touching together), 'contagion' (touching and spreading), 'intact' (untouched), and 'tact' (the touch of social sensitivity) all share the same ancient root.