réfraction

Forms

réfraction f (plural réfractions)^[1]

Etymology

It is borrowed from Late Latin refrāctiō (“turning back, reversal”), formed on refrāctum, the supine of Latin refringō (“to break up”).^[2][3][4][5] That verb is made of the intensive re- and frangō (“to break”), and was already used of the breaking of the sun's rays.^[3][6] The word is related to réfringent and fraction.^[3]

Earliest recorded meaning

The first record is in Mahieu le Vilain's translation of Aristotle's Meteorology, dated 1270 but known from a manuscript of about 1369, in the sense of the bending of a ray as it passes into a medium of different density.^[2][4] Bloch and Wartburg date the word to about 1360.^[6]

Semantic evolution

Littré quotes Paré in the 16th century using refraction of the movement of humours in the body.^[7] In 1644 Descartes used it for the deflection of one body by another, and in astronomy for the bending of a star's light by the atmosphere.^[2][3]

The word spread at the beginning of the 18th century under the influence of the English refraction as used by Newton, now clearly set apart from réflexion.^[3][8] From it came phrases such as indice de réfraction (1756) and réfraction astronomique (1690).^[3][4] In the 20th century it was extended to acoustics, for the change of direction of a sound wave, and to physiology, for the refractive power of the eye (1964).^[3][4] The derivative réfractionniste (1964), a specialist who measures and corrects ocular refraction, was probably formed after the English refractionist.^[2][3]

Timeline

• 1270 – Mahieu le Vilain uses it in optics.^[2][4][8]
• 16th century – Paré uses it of the humours of the body.^[7]
• 1644 – Descartes uses it for the deflection of one body by another.^[2]
• 1690 – Furetière records réfraction astronomique.^[4]
• early 18th century – It spreads under the influence of Newton's English.^[3][8]
• 1739 – The verb réfracter is formed.^[6]
• 1756 – Indice de réfraction is recorded.^[3]
• 1964 – Larousse records the sense “refractive power of the eye” and the derivative réfractionniste.^[4][2]

Meanings

Noun

1. (physics) Refraction, the change of direction of a light ray or other wave as it passes from one medium into another in which it travels at a different speed: l'angle de réfraction, l'indice de réfraction.^[9][2][10]
2. Double réfraction: the splitting of a ray into two on passing through certain crystals.^[9][4][7]
3. Réfraction astronomique or atmosphérique: the bending of light from a star by the Earth's atmosphere.^[2][4]
4. (physiology) The refractive power of the eye.^[4][3]

Word family

• réfracter
• réfractionniste

Related words

• réfringent
• fraction
• réflexion
• Latin refringō
• English refraction

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i Trésor de la langue française informatisé (2004), ATILF – CNRS & Université de Lorraine, atilf.fr/tlfi; electronic version of Imbs, Paul; Quemada, Bernard, eds. (1971–1994), Trésor de la langue française, Paris: CNRS / Gallimard
3. ^ a b c d e f g h i j k Rey, Alain, ed. (1992), Dictionnaire historique de la langue française, Paris: Le Robert
4. ^ a b c d e f g h i j Guilbert, Louis; Lagane, René; Niobey, Georges, eds. (1971–1978; 1989), Grand Larousse de la langue française, Paris: Larousse
5. ^ Wartburg, Walther von, et al. (1922–2002), Französisches Etymologisches Wörterbuch, 25 vols., Bonn / Leipzig / Basel: Klopp / Teubner / Zbinden, p. 10, 194b
6. ^ a b c Bloch, Oscar; Wartburg, Walther von (1989), Dictionnaire étymologique de la langue française, 8th ed., Paris: Presses universitaires de France
7. ^ a b c Littré, Émile (1873–1877), Dictionnaire de la langue française, 4 vols. and supplement, Paris: Hachette
8. ^ a b c Rey, Alain, ed. (2005), Le Grand Robert de la langue française, electronic version, Paris: Le Robert
9. ^ a b Rey-Debove, Josette; Rey, Alain, eds. (2007), Le Petit Robert de la langue française, Paris: Le Robert
10. ^ Dictionnaire Le Robert en ligne, dictionnaire.lerobert.com (accessed 2024)