torus

Borrowed from Latin torus (“a round, swelling, elevation, protuberance”).

• (Received Pronunciation) IPA^(key): /ˈtɔː.ɹəs/
• (General American, Canada) IPA^(key): /ˈtɔɹəs/, [ˈtɔ.ɹəs]

  • Audio (US):

    (file)

• (General Australian, New Zealand) IPA^(key): /ˈtoː.ɹəs/

  • Audio (Queensland):

    (file)

• Rhymes: -ɔːɹəs
• Homophone: Taurus (horse–hoarse merger)

torus (plural tori or toruses)

2. (geometry) The standard representation of such a space in 3-dimensional Euclidean space: a surface or solid formed by rotating a closed curve, especially a circle, about a line which lies in the same plane but does not intersect it (e.g. like a ring doughnut).

   Hypernym: toroid

   1. (topology) A topological space which is a product of two circles.

      Hyponym: solid torus

      A 4-variable Karnaugh map can be thought of, topologically, as being a torus.

      1. (topology, in combination, n-torus, 4-torus, etc.) The product of the specified number of circles.
   2. A ring-shaped object, especially a large ring-shaped chamber used in physical research.
4. (architecture) A large convex molding, typically semicircular in cross section, which commonly projects at the base of a column and above the plinth.
5. (anatomy) A rounded ridge of bone or muscle, especially one on the occipital bone.
7. (botany) The end of the peduncle or flower stalk to which the floral parts (or in the Asteraceae, the florets of a flower head) are attached.

   Synonyms: receptacle, thalamus

9. (botany) The thickening of a membrane closing a wood-cell pit (as of gymnosperm tracheids) having the secondary cell wall arched over the pit cavity.

• torus tubarius

• annulus
• hoop

• “torus”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.
• “torus”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.

• Rusto, Stour, Sutor, Tours, roust, routs, stour, sutor, tours

From Latin torus.

• Audio:

  (file)

• Hyphenation: to‧rus

torus m (plural torussen, diminutive torusje n)

1. (geometry) torus

From Latin torus.

• IPA^(key): /ˈtorus/, [ˈt̪o̞rus̠]
• IPA^(key): /ˈtoːrus/, [ˈt̪o̞ːrus̠] (proscribed)
• Rhymes: -orus
• Syllabification^(key): to‧rus
• Hyphenation^(key): to‧rus

torus

1. (geometry, topology) torus

• IPA^(key): /ˈtorus/, [ˈt̪o̞rus̠]
• Rhymes: -orus
• Syllabification^(key): to‧rus
• Hyphenation^(key): to‧rus

torus

1. second-person singular present imperative of torua (with enclitic -s)

• ruots., rusto, turso

• torum, thorus

Of uncertain origin.

De Vaan proposes a tentative derivation from a Proto-Indo-European *torh₂-os, from *terh₂- (“to cross, go through”). This is formally and semantically solid, though there is little linguistic evidence to support it.

An older theory by Leumann derived the word from sternō (“to spread”), itself from Proto-Indo-European *sterh₃- (“to spread, extend”), but the connection between the two Latin words is semantically dubious (one would expect torus to be derived from a verb meaning "to turn" or "to knot" rather than "to spread").^[1]

• (Classical Latin) IPA^(key): [ˈtɔ.rʊs]
• (modern Italianate Ecclesiastical) IPA^(key): [ˈt̪ɔː.rus]

torus m (genitive torī); second declension

1. round, swelling, bulging place; elevation, protuberance
2. bulge, knot
3. (zootomy, usually poetic) muscular or fleshly part, muscle, brawn of an animal bodies
   1. (transferred sense, botany) bulge, thickness of trees
4. raised ornament, knot on a garland
5. (usually poetic) bolster, cushion; bed, couch, sofa

   Synonym: pulvīnar

   1. marriage bed
      • 8 CE, Ovid, Fasti 3.483–484:

        ausus es ante oculōs adductā paelice nostrōs
        tam bene compositum sollicitāre torum?

        Have you dared, by bringing your mistress before my eyes,
        to disturb our marriage bed so very well-composed?
        (Ariadne accuses her husband of infidelity.)

   2. (transferred sense, figuratively) marriage (sometimes any sexual relationship)

      Synonym: thalamus

6. embankment, elevation of earth
7. (architecture) large round molding at the base of a column

Second-declension noun.

• toral
• torāria
• torōsus (adjective)
• torulus (diminutive)

• “torus”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• “torus”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• torus in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.
• “torus”, in The Perseus Project (1999) Perseus Encyclopedia‎^[1]
• “torus”, in Harry Thurston Peck, editor (1898), Harper’s Dictionary of Classical Antiquities, New York: Harper & Brothers
• “torus”, in William Smith et al., editor (1890), A Dictionary of Greek and Roman Antiquities, London: William Wayte. G. E. Marindin

• sutor

torus c

1. (geometry, topology) torus; a shape consisting of a ring, or an object of the same topology residing in a space of higher dimension; especially considered as a Cartesian product of two circles in a four-dimensional space

• flat torus

• torus in Svenska Akademiens ordbok (SAOB)

• oturs