annulus

From Wiktionary, the free dictionary
Archived revision by WingerBot (talk | contribs) as of 05:24, 10 October 2019.
Jump to navigation Jump to search

English

Etymology

Borrowed from Latin annulus.

Noun

annulus (plural annuluses or annuli)

  1. A ring- or donut-shaped area or structure.
  2. (geometry) The region in a plane between two concentric circles of different radius.
  3. (topology) Any topological space homeomorphic to the region in a plane between two concentric circles of different radius.
  4. (astronomy) The ring of the sun not covered by the moon in an annular solar eclipse.
  5. (botany) Structure in a fern that consists of differentially thick-walled cells on a sporangium that bend and distort as a result of drying.
  6. (mycology) The membranous remnants of a partial veil which leaves a ring on the stem of a mushroom.
  7. (oil and gas production) The space contained between the centre well bore and any external tubing. Sometimes used for separated gas flow.

Synonyms

Hyponyms

  • (ring-shaped structure): torus

Derived terms

Translations


Latin

Pronunciation

Noun

ānnulus m (genitive ānnulī); second declension

  1. Alternative form of ānulus

Declension

Second-declension noun.

Case Singular Plural
Nominative ānnulus ānnulī
Genitive ānnulī ānnulōrum
Dative ānnulō ānnulīs
Accusative ānnulum ānnulōs
Ablative ānnulō ānnulīs
Vocative ānnule ānnulī

References

  • annulus in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
  • annulus”, in Harry Thurston Peck, editor (1898), Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
  • annulus”, in William Smith et al., editor (1890), A Dictionary of Greek and Roman Antiquities, London: William Wayte. G. E. Marindin