quadratique

Forms

quadratique (plural quadratiques)^[1]

Etymology

It is formed in learned use from Latin quadrātus (“squared, square”), with the suffix -ique.^[2][3][4] The Latin word is the past participle of quadrō (“to make square”), from quadrus (“square”).^[1] Littré likewise derives it from this Latin adjective.^[5] Compare the English word quadratic, used in mathematics from the 1660s.^[6]

Earliest recorded meaning

It first appears in the Encyclopédie in 1765, in équation quadratique, an equation of the second degree.^[2][4]

Semantic evolution

From the phrase équation quadratique the adjective widened to anything relating to a square or raised to the second power: the TLFi dates this from the Académie's supplement of 1842, the GLLF from the Larousse of 1875.^[2][4] In 1859 Bouillet used it in crystallography,^[2][7] and système quadratique names the crystal system with the symmetry of a right prism on a square base (1932).^[2][4] The Petit Robert dates the word from 1751.^[7]

Timeline

• 1765 – Équation quadratique in the Encyclopédie.^[2][4]
• 1842 – The Académie's supplement records the sense “relating to the square”.^[2]
• 1859 – Bouillet uses it in crystallography.^[2]
• 1932 – The Larousse records système quadratique.^[2][4]

Meanings

Adjective

1. (mathematics) Of the second degree, raised to the square: moyenne quadratique, forme quadratique.^[2][7]
2. Équation quadratique: a quadratic equation.^[4][5]
3. (crystallography) Of the crystal system with three axes at right angles and a square base, or of a mineral in it.^[7][2]

Related words

• carré
• cadrat
• Latin quadrātus
• English quadratic

References

1. ^ a b c d Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k 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. ^ Rey, Alain, ed. (2005), Le Grand Robert de la langue française, electronic version, Paris: Le Robert
4. ^ a b c d e f g Guilbert, Louis; Lagane, René; Niobey, Georges, eds. (1971–1978; 1989), Grand Larousse de la langue française, Paris: Larousse
5. ^ a b Littré, Émile (1873–1877), Dictionnaire de la langue française, 4 vols. and supplement, Paris: Hachette
6. ^ Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
7. ^ a b c d Rey-Debove, Josette; Rey, Alain, eds. (2007), Le Petit Robert de la langue française, Paris: Le Robert