annulus

• POS: Noun
• HYPHEN: an=nu=lus

CIDE DICTIONARY

annulus, n. [L.].

•  A ring; a ringlike part or space.  [1913 Webster]
•  A space contained between the circumferences of two circles, one within the other.  [1913 Webster]
•  Ring-shaped structures or markings, found in, or upon, various animals.  [1913 Webster]

OXFORD DICTIONARY

annulus, n. (pl. annuli) esp. Math. & Biol. a ring.

Etymology

L an(n)ulus

ROGET THESAURUS

annulus

Circularity

N circularity, roundness, rotundity, circle, circlet, ring, areola, hoop, roundlet, annulus, annulet, bracelet, armlet, ringlet, eye, loop, wheel, cycle, orb, orbit, rundle, zone, belt, cordon, band, contrate wheel, crown wheel, hub, nave, sash, girdle, cestus, cincture, baldric, fillet, fascia, wreath, garland, crown, corona, coronet, chaplet, snood, necklace, collar, noose, lasso, lassoo, ellipse, oval, ovule, ellipsoid, cycloid, epicycloid, epicycle, semicircle, quadrant, sextant, sector, sphere, round, rounded, circular, annular, orbicular, oval, ovate, elliptic, elliptical, egg-shaped, pear-shaped, cycloidal, spherical, I watched the little circles die.