Word Study
antrum
CIDE DICTIONARY
antrum, n. [L., fr. Gr. .].
A cavern or cavity, esp. an anatomical cavity or sinus Huxley. [1913 Webster]
OXFORD DICTIONARY
antrum, n. (pl. antra) Anat. a natural chamber or cavity in the body, esp. in a bone.
Derivative
antral adj.
Etymology
L f. Gk antron cave
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