annulus

noun an·nu·lus \ˈan-yə-ləs\

plural an·nu·li\-ˌlī, -(ˌ)lē\ also an·nu·lus·es

Definition of ANNULUS

: ring

: a part, structure, or marking resembling a ring: as

a : a line of cells around a fern sporangium that ruptures the sporangium by contracting

b : a growth ring (as on the scale of a fish) that is used in estimating age

Medieval Latin, from Latin anulus finger ring, from anus ring — more at anus

First Known Use: 1563

Medical Dictionary

noun an·nu·lus \ˈan-yə-ləs\

plural an·nu·li \-ˌlī\ also an·nu·lus·es

: a ringlike part, structure, or marking; especially : any of various ringlike anatomical parts (as the inguinal ring)

Next Word in the Dictionary: annunciatePrevious Word in the Dictionary: AnnulosaAll Words Near: annulus

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