Word Study
cingulum
CIDE DICTIONARY
cingulum, n. [L., a girdle.].
A distinct girdle or band of color; a raised spiral line as seen on certain univalve shells. [1913 Webster]
OXFORD DICTIONARY
cingulum, n. (pl. cingula) Anat. a girdle, belt, or analogous structure, esp. a ridge surrounding the base of the crown of a tooth.
Etymology
L, = belt
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