Origins
The English word 'right' is one of the most semantically loaded words in the language, carrying simultaneous meanings of directionality (the right hand), moral correctness (the right thing to do), legal entitlement (human rights), and accuracy (the right answer). All these senses trace to a single Proto-Indo-European root, *h₃reǵ-, meaning 'to move in a straight line,' 'to direct,' or 'to stretch out straight.' The word's extraordinary range of meaning grew from this simple spatial concept of straightness.
Old English 'riht' meant 'straight,' 'just,' 'proper,' and 'the right-hand side' — all four modern senses already bundled together over a thousand years ago. The Proto-Germanic ancestor *rehtaz preserved the PIE meaning faithfully, and cognates across the Germanic family confirm the consistency: German 'recht' (right, law, justice), Dutch 'recht' (right, straight, law), Old Norse 'réttr' (right, correct, just), and Gothic 'raihts' (straight, right).
The Indo-European family of this root is one of the largest and most important in comparative linguistics. Latin 'rēctus' (straight, upright, correct) gave English 'rectify,' 'rectangle,' 'erect,' and 'correct' (from 'con-' + 'regere'). Latin 'rēx' (king — literally 'the one who directs/rules in a straight line') produced 'regal,' 'regent,' 'regime,' 'regicide,' and 'royal' (through Old French). Latin 'rēgula' (straight stick, rule) gave 'regular,' 'regulate,' and 'rule' itself. Latin 'regiō' (direction, region) produced 'region.' Sanskrit 'ṛjú' (straight, honest) and 'rājan' (king) continue the same root in the Indo-Aryan branch. Celtic languages preserve it in Old Irish 'ríg' (king) and 'recht' (law).
Latin Roots
The convergence of 'right-hand' and 'morally correct' in the same word is not unique to English — it appears across the Indo-European family and beyond. Latin 'dexter' (right-hand) also meant 'skillful' and 'favorable' (giving English 'dexterous'). French 'droit' means both 'right-hand' and 'law/legal right.' This pattern reflects the deep cultural privileging of right-handedness: the right hand was the sword hand, the oath-swearing hand, the hand of skill and authority. The left, by contrast, was sinister (literally — Latin 'sinister' means 'left').
The phonological development from Old English 'riht' to Modern English 'right' involves the loss of the velar fricative /x/ (the 'ch' sound in German 'Recht' or Scottish 'loch'). In Old and Middle English, 'riht' was pronounced with this throaty consonant: something like /rɪxt/. During the Middle English period, the fricative was lost, but the preceding vowel was lengthened and eventually diphthongized in the Great Vowel Shift, producing the modern /ɹaɪt/. The silent 'gh' in the modern spelling is a fossil of this lost pronunciation — the same ghost consonant haunts 'night,' 'light,' 'might,' 'sight,' and 'thought.'
The political sense of 'the right' mirrors that of 'the left': both date to the seating arrangement of the French National Assembly in 1789, where conservative supporters of the monarchy sat to the president's right. In this context, 'right' acquired its modern political meaning of 'conservative' or 'traditional,' a meaning that resonates — perhaps accidentally, perhaps not — with the word's ancient association with authority, order, and established rule.
French Influence
The legal sense of 'right' (as in 'human rights,' 'civil rights') developed from the moral sense through Old French and medieval Latin 'rectum' (what is right, justice, a legal entitlement). The American Bill of Rights, the French Declaration of the Rights of Man, and the Universal Declaration of Human Rights all use the word in this derived legal sense — tracing, through centuries of philosophical and legal development, back to the PIE concept of straightness as the foundation of justice.