torus

See also: Torus

English

WOTD – 10 April 2007

A geometrical torus

Etymology

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

Pronunciation

• (Received Pronunciation) IPA^(key): /ˈtɔː.ɹəs/
• (General American, Canada) IPA^(key): /toʊ̯ɹəs/, (horse–hoarse merger) /ˈtɔ.ɹəs/

  • Audio (US):

    (file)

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

  • Audio (Queensland):

    (file)

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

Noun

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).

   Synonym: toroid (torus sense)

   Hypernym: toroid (general sense)

   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.
   • 2010 March, Andrés S. García-García, José-María Martínez-González, Rafael Gómez-Font, Ángeles Soto-Rivadeneira, Lucia Oviedo-Roldán, “Current status of the torus palatinus and torus mandibularis”, in Oral Surgery‎^[1], volume 15, number 2, page 353:

     While there is a hereditary component to tori, this does not explain all cases. Tori tend to appear more frequently during middle age of life; the torus palatinus is more commonly observed in females, but this is not the case with the torus mandibularis. Certain ethnic groups are more prone to one torus or the other.

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.

Derived terms

• de Bruijn torus
• hypertorus
• keratotorus
• nanotorus
• polytorus
• subtorus
• supertorus
• toric
• toroid

Related terms

• torus tubarius

Translations

shape in 3-dimensional Euclidean space

• Albanian: torusi
• Arabic: طَارَة (ar) m (ṭāra)
• Basque: toru
• Belarusian: тор m (tor)
• Bulgarian: тор m (tor)
• Catalan: tor (ca) m
• Chinese:

  Mandarin: 環面 / 环面 (zh) (huánmiàn)

• Czech: torus (cs) m
• Danish: torus (da) c
• Dutch: torus (nl) m
• Esperanto: toro (eo)
• Estonian: toor
• Finnish: torus (fi)
• French: tore (fr) m
• Galician: toro (gl) m
• German: Torus (de) m
• Greek: τόρος (el) m (tóros)
• Hebrew: טורוס m (torus)
• Hungarian: tórusz (hu)
• Ido: toro (io)
• Italian: toro (it) m
• Japanese: トーラス (ja) (tōrasu)
• Korean: 원환면 (wonhwanmyeon)
• Latvian: tors m
• Lithuanian: toras m
• Macedonian: тор m (tor)
• Māori: tarawhiti
• Norwegian:

  Bokmål: torus m

  Nynorsk: torus m

• Polish: torus (pl) m, armila f
• Portuguese: toro (pt) m
• Romanian: tor (ro) n
• Russian: тор (ru) m (tor)
• Serbo-Croatian:

  Cyrillic: торус m

  Latin: torus (sh) m

• Slovak: torus m
• Slovene: torus m
• Spanish: toro (es) m
• Swedish: torus (sv) c
• Turkish: simit (tr)
• Ukrainian: тор (uk) m (tor)
• Vietnamese: khối xuyến

topological space

• Chinese:

  Mandarin: 環面 / 环面 (zh) (huánmiàn)

• Esperanto: toro (eo)
• Finnish: torus (fi)
• French: tore (fr)
• Japanese: トーラス (ja) (tōrasu)
• Polish: torus (pl) m
• Russian: тор (ru) m (tor)
• Spanish: toro (es) m

in combination, product of circles

• Finnish: torus (fi)
• Polish: torus (pl) m

convex molding

• Catalan: tor (ca) m, bossell (ca) m
• Finnish: torus (fi), vannikka
• French: tore (fr) m
• German: Wulst (de) m
• Italian: toro (it) m
• Polish: torus (pl) m

receptacle

• Chinese:

  Mandarin: 花托 (zh) (huātuō)

• Finnish: kukkapohjus (fi)
• Polish: torus (pl) m

The translations below need to be checked and inserted above into the appropriate translation tables. See instructions at Wiktionary:Entry layout § Translations.

Translations to be checked

• Greek: ^{(please verify)} τόρος (el) m (tóros)

See also

• annulus
• hoop

References

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

Anagrams

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

Dutch

Etymology

From Latin torus.

Pronunciation

• Audio:

  (file)

• Hyphenation: to‧rus

Noun

torus m (plural torussen, diminutive torusje n)

1. (geometry) torus

Finnish

Etymology 1

From Latin torus.

Pronunciation

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

Noun

torus

1. (geometry, topology) torus

Declension

Inflection of torus (Kotus type 39/vastaus, no gradation)
nominative		torus	torukset
genitive		toruksen	torusten toruksien
partitive		torusta	toruksia
illative		torukseen	toruksiin
		singular	plural
nominative		torus	torukset
accusative	nom.	torus	torukset
	gen.	toruksen
genitive		toruksen	torusten toruksien
partitive		torusta	toruksia
inessive		toruksessa	toruksissa
elative		toruksesta	toruksista
illative		torukseen	toruksiin
adessive		toruksella	toruksilla
ablative		torukselta	toruksilta
allative		torukselle	toruksille
essive		toruksena	toruksina
translative		torukseksi	toruksiksi
abessive		toruksetta	toruksitta
instructive		—	toruksin
comitative		See the possessive forms below.

Possessive forms of torus (Kotus type 39/vastaus, no gradation)

first-person singular possessor singular plural nominative torukseni torukseni accusative nom. torukseni torukseni gen. torukseni genitive torukseni torusteni toruksieni partitive torustani toruksiani inessive toruksessani toruksissani elative toruksestani toruksistani illative torukseeni toruksiini adessive toruksellani toruksillani ablative torukseltani toruksiltani allative torukselleni toruksilleni essive toruksenani toruksinani translative toruksekseni toruksikseni abessive toruksettani toruksittani instructive — — comitative — toruksineni second-person singular possessor singular plural nominative toruksesi toruksesi accusative nom. toruksesi toruksesi gen. toruksesi genitive toruksesi torustesi toruksiesi partitive torustasi toruksiasi inessive toruksessasi toruksissasi elative toruksestasi toruksistasi illative torukseesi toruksiisi adessive toruksellasi toruksillasi ablative torukseltasi toruksiltasi allative toruksellesi toruksillesi essive toruksenasi toruksinasi translative torukseksesi toruksiksesi abessive toruksettasi toruksittasi instructive — — comitative — toruksinesi first-person plural possessor singular plural nominative toruksemme toruksemme accusative nom. toruksemme toruksemme gen. toruksemme genitive toruksemme torustemme toruksiemme partitive torustamme toruksiamme inessive toruksessamme toruksissamme elative toruksestamme toruksistamme illative torukseemme toruksiimme adessive toruksellamme toruksillamme ablative torukseltamme toruksiltamme allative toruksellemme toruksillemme essive toruksenamme toruksinamme translative torukseksemme toruksiksemme abessive toruksettamme toruksittamme instructive — — comitative — toruksinemme second-person plural possessor singular plural nominative toruksenne toruksenne accusative nom. toruksenne toruksenne gen. toruksenne genitive toruksenne torustenne toruksienne partitive torustanne toruksianne inessive toruksessanne toruksissanne elative toruksestanne toruksistanne illative torukseenne toruksiinne adessive toruksellanne toruksillanne ablative torukseltanne toruksiltanne allative toruksellenne toruksillenne essive toruksenanne toruksinanne translative torukseksenne toruksiksenne abessive toruksettanne toruksittanne instructive — — comitative — toruksinenne third-person possessor singular plural nominative toruksensa toruksensa accusative nom. toruksensa toruksensa gen. toruksensa genitive toruksensa torustensa toruksiensa partitive torustaan torustansa toruksiaan toruksiansa inessive toruksessaan toruksessansa toruksissaan toruksissansa elative toruksestaan toruksestansa toruksistaan toruksistansa illative torukseensa toruksiinsa adessive toruksellaan toruksellansa toruksillaan toruksillansa ablative torukseltaan torukseltansa toruksiltaan toruksiltansa allative torukselleen toruksellensa toruksilleen toruksillensa essive toruksenaan toruksenansa toruksinaan toruksinansa translative toruksekseen torukseksensa toruksikseen toruksiksensa abessive toruksettaan toruksettansa toruksittaan toruksittansa instructive — — comitative — toruksineen toruksinensa

Etymology 2

Pronunciation

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

Verb

torus

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

Anagrams

• ruots., rusto, turso

Latin

Alternative forms

• torum, thorus

Etymology

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").

Pronunciation

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

Noun

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, Ovidius, 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

Inflection

Second-declension noun.

	singular	plural
nominative	torus	torī
genitive	torī	torōrum
dative	torō	torīs
accusative	torum	torōs
ablative	torō	torīs
vocative	tore	torī

Derived terms

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

Descendants

Descendants

• Asturian: tueru
• → English: torus
• French: toron, → tore (learned)
• → Galician: toro (learned)
• → Italian: toro (learned)
• → Portuguese: toro (learned)
• Spanish: tuero, → toro (learned)

References

• “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^[2]
• “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

Anagrams

• sutor

Swedish

Noun

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

Declension

Declension of torus

		nominative	genitive
singular	indefinite	torus	torus
	definite	torusen	torusens
plural	indefinite	torusar	torusars
	definite	torusarna	torusarnas

Related terms

• flat torus

References

• “torus”, in Svenska Akademiens ordbok [Dictionary of the Swedish Academy] (in Swedish)

Anagrams

• oturs