Etymologically
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sinus

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Pronunciation

  • IPA (Classical): [ˈsɪ.nʊs][1]
  • IPA (Ecclesiastical): [ˈsiː.nus][1]

Forms

sinus m (genitive sinūs); fourth declension[1]

Etymology

It is inherited from Proto-Italic *sinu-, probably inherited from Proto-Indo-European *sinu-, and probably related to Albanian gji (“breast”) (from ⟨*sin-⟩).[2][1] If so, Sanskrit सानु (sā́nu, “back, ridge”) cannot be cognate, since it lacks the ⟨*-i-⟩.[2] The OLD calls the origin doubtful and mentions the Albanian word as a possibility;[3][4] Köbler calls it unclear.[3][4] De Vaan finds no further etymology.[2]

Earliest recorded meaning

De Vaan dates it from Terence,[2] who has hīcine nōn gestandus in sinūst?, “isn't he to be carried in one's bosom?”, of a person much loved.[3]

Semantic evolution

Sinus is the fold formed by a garment looped over the breast, and the breast it covers; it is the bosom or arms in which a person is held in affection, and figuratively a refuge (in sinū gaudēre, “to rejoice in secret”).[3][5][1] The fold of the toga served as a pocket, so it also means one's purse or resources.[3][1] It is the breast as the seat of feelings, the inmost part of a place, the bellying of a sail, any hollow or curve, and a bay or gulf.[3][5][1] Döderlein contrasts gremium, the lap and a symbol of a mother's care, with sinus, the bosom and a symbol of protection.[6]

In Church Latin it is “breast, bosom; bay”.[7] In the 12th century Gherardo of Cremona used it for the sine of an angle, rendering an Arabic word for a fold or pocket.[1][8] English sinus (early 15th century, a cavity in the body) and sine (1590s) come from it.[8]

Timeline

  • 190–159 BC – Terence: hīcine nōn gestandus in sinūst?.[3][4]
  • 81–43 BC – Cicero: the fold of the toga as a pocket for letters.[3][4]
  • mid-12th century – Gherardo of Cremona uses it for the sine.[8][1]
  • early 15th century – Borrowed into English as sinus in anatomy.[8]

Meanings

Noun

  1. A fold of a garment, especially of the toga over the breast; the breast.[3][5][1]
  2. The bosom, embrace; a refuge, shelter.[3][1][7]
  3. A pocket; one's purse, resources.[3][1]
  4. The breast as the seat of feelings; the inmost part of a place.[3][1]
  5. The swelling of a sail.[3]
  6. A hollow, curve, cavity.[3][5][1]
  7. A bay, gulf.[1][7]
  8. (Medieval Latin, mathematics) The sine of an angle.[1]

Word family

  • sinuō
  • sinuōsus
  • īnsinuō
  • gremium
  • English sinus
  • English sine

Usage notes

A separate word sīnus (second declension), a large drinking vessel, is a pre-classical form of sīnum, found in Plautus.[3][5][1][4]

References

  1. ^ a b c d e f g h i j k l m n o p q Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
  3. ^ a b c d e f g h i j k l m n o Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  4. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  5. ^ a b c d e Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  6. ^ Döderlein, Ludwig (1874), Döderlein’s Hand-book of Latin Synonymes, tr. H. H. Arnold, Andover: W. F. Draper
  7. ^ a b c Stelten, Leo F. (1995), Dictionary of Ecclesiastical Latin, Peabody, Mass.: Hendrickson
  8. ^ a b c d Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com