Annulus (or anulus) or annular indicates a ring- or donut-shaped area or structure. It may refer to:
Human anatomy
* ''
Anulus fibrosus disci intervertebralis'', spinal structure
*
Annulus of Zinn, a.k.a. annular tendon or ''anulus tendineus communis'', around the optic nerve
*
Annular ligament (disambiguation)
* ''Digitus anularis'', a.k.a.
ring finger
The ring finger, third finger, fourth finger, leech finger, or annulary is the fourth digit of the human hand, located between the middle finger and the little finger.
Sometimes the term ring finger only refers to the fourth digit of a left-h ...
* ''Anulus ciliaris'', a.k.a.
ciliary body
* ''Anulus femoralis'', a.k.a.
femoral ring
* ''Anulus inguinalis superficialis'', a.k.a.
superficial inguinal ring
* ''Anulus inguinalis profundus'', a.k.a.
deep inguinal ring
* ''Anuli fibrosi cordis'', a.k.a.
fibrous rings of heart
* ''Anulus umbilicalis '', a.k.a.
umbilical ring
Other
*
Annulus (construction), outer gear ring in an
epicyclic gearing
An epicyclic gear train (also known as a planetary gearset) consists of two gears mounted so that the center of one gear revolves around the center of the other. A carrier connects the centers of the two gears and rotates the planet and sun gea ...
*
Annulus (botany), structure on fern and moss sporangia
*
Annular lake, a ring-shaped lake caused by meteor impact
*
Annulus (mathematics), the shape between two concentric circles
*
Annulus (mycology), structure on mushroom
*
Annulus (firestop), site of construction issue
*
Annular piston, a ring-shaped piston
*
Annulus (well), void between concentric cylinders
*
Annular blowout preventer, device for sealing oil and gas wells
*
Annulation, type of ring-producing chemical reaction
See also
*
*
*
Annulet (disambiguation)
*
Annular eclipse
*
Annular tropical cyclone
* Annular combustor,
design option in engine
*
Ring (disambiguation)
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