annuluses
Doughnut-shaped regions mathematically
Annuluses is the plural of annulus, a ring-shaped structure or the region between two concentric circles.
The term appears in mathematics, anatomy, and biology: The annuluses of the tree trunk revealed its age.
The Latinate plural annuli is equally common in technical contexts.
Rings that prevent leakage
- sealsAquatic whiskered mammals
- O-ringsLoop-shaped mechanical seals
- washersFlat discs under nuts
- spacersItems creating measured gaps
bearings · bushings · flanges · pipe fittings · rubber rings · piston rings
Annual layers in wood
- tree ringsAnnual wood layers
- annual ringsYearly wood layers
- dendrochronologyDating via growth rings
- woody stemsHard plant supports
xylem · cross-sections · seasonal growth · fairy rings · spore-bearing
Circular bands worn
- concentric circlesRings with shared midpoint
- areasBounded sections of space
- radiiPlural of circle's half-diameter
- inner circlesTrusted, influential associates
Circular bands worn
- heart valvesTissue controlling blood direction
- intervertebral discsCushioning tissue between vertebrae
- cardiac surgeryProcedures on the heart
- collagenStructural body protein
Icy debris encircling planet
- planetary ringsDisk-shaped debris orbiting planets
- protoplanetary disksGas and dust orbiting newborn stars
- ring systemsOrbiting debris disks
- ice particlesFrozen water fragments
gaskets
Rings that prevent leakage
spacers · bearings · bushings · flanges · pipe fittings · rubber rings · piston rings
growth rings
Annual layers in wood
- tree ringsAnnual wood layers
- annual ringsYearly wood layers
- dendrochronologyDating via growth rings
woody stems · xylem · cross-sections · seasonal growth · fairy rings · spore-bearing
rings
Circular bands worn
- concentric circlesRings with shared midpoint
- areasBounded sections of space
- radiiPlural of circle's half-diameter
inner circles · washers · donuts · two-dimensional · circumferences
rings
Circular bands worn
- heart valvesTissue controlling blood direction
- intervertebral discsCushioning tissue between vertebrae
- cardiac surgeryProcedures on the heart
Saturn rings
Icy debris encircling planet
- planetary ringsDisk-shaped debris orbiting planets
- protoplanetary disksGas and dust orbiting newborn stars
- ring systemsOrbiting debris disks
ice particles · asteroid belts · tidal forces · shepherd moons