impair

Forms

impair (feminine impaire, masculine plural impairs, feminine plural impaires)^[1] First written impar (1484), remade as impair after pair by 1521.^[2][3][4]

Etymology

It is borrowed from Latin impār (“unequal, unlike, odd”), an adjective and noun, refashioned after pair.^[2][3][5] The Latin word is formed from in- (“not”) and pār (“equal”), of which it is the opposite.^[6][5] Horace already uses the Latin phrase for playing odd or even.^[2]

Old French had rendered the idea as nonper, already the name of a 13th-century dice game.^[2][5]

Earliest recorded meaning

It is first recorded in 1484, in Nicolas Chuquet's Triparty, in the form impar, of an odd number.^[2][6]

Semantic evolution

Introduced in arithmetic as the opposite of pair, the adjective passed into games, where it was also used as a noun from 1765, as in the game of pair ou non.^[2][5] By extension it meant “bearing an odd number”, as in années impaires (1798) and vers impairs in poetry.^[5][6] In the natural sciences it describes an organ that has no symmetrical double (1805, Cuvier), and in botany a leaflet (1811).^[5][6]

Since the middle of the 19th century (1858, Augier) the noun has meant a shocking or damaging blunder.^[2][5][7] This sense probably comes from the gaming phrase faire un double impair “to take odd twice running by mistake”.^[5][7] Esnault instead explained it as the opposite of pair “straight, frank”, a sense taken from the phrase parler pair “to speak plainly”.^[2][5]

Timeline

• 1484 – Impar appears in Chuquet's Triparty.^[2]
• 1521 – The form impair is recorded.^[2][4]
• 1765 – The Encyclopédie uses it as a noun in the game of odd or even.^[2]
• 1798 – The Académie records it of things bearing an odd number.^[6][5]
• 1805 – Cuvier uses it of an unpaired muscle.^[5]
• 1858 – Augier uses the noun for a blunder.^[2][5]

Meanings

Adjective

1. (arithmetic) odd: not divisible by two into whole numbers, as in nombre impair.^[7][2][1]
2. (mathematics) Of a function: odd, changing sign when the variable does.^[7][1]
3. Bearing an odd number: jours impairs, le côté impair de la rue;^[7][6] vers impairs have an odd number of syllables.^[7][6]
4. (natural sciences) Single, having no symmetrical double, as a leaflet (foliole impaire) or, formerly, an organ such as the heart.^[7][8]

Noun

1. (games) The odd numbers, at roulette and similar games: jouer l'impair.^[7][2]
2. A shocking or damaging blunder, a gaffe: commettre un impair.^[7][2][1]

Related words

• pair
• imparité
• Latin impār

References

1. ^ a b c d e Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o 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 Bloch, Oscar; Wartburg, Walther von (1989), Dictionnaire étymologique de la langue française, 8th ed., Paris: Presses universitaires de France
4. ^ a b Rey, Alain, ed. (2005), Le Grand Robert de la langue française, electronic version, Paris: Le Robert
5. ^ a b c d e f g h i j k l Rey, Alain, ed. (1992), Dictionnaire historique de la langue française, Paris: Le Robert
6. ^ 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
7. ^ a b c d e f g h i Rey-Debove, Josette; Rey, Alain, eds. (2007), Le Petit Robert de la langue française, Paris: Le Robert
8. ^ Littré, Émile (1873–1877), Dictionnaire de la langue française, 4 vols. and supplement, Paris: Hachette