A cavity into which, in certain bryozoans, the esophagus and anus open.(noun)
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Use "vestibulum" in a sentence
"Bray's _History of Surrey_ (vol.i. p. 314.) without any notice of its contents, is preserved in the upper chamber of a building on the north side of the chancel, erected in 1513, and designated as a "vestibulum" in a contemporary inscription."
"Nam vel nulla ac orci vestibulum mattis fringilla sit amet lectus."
"Morbi pharetra vulputate nulla, nec elementum tortor vestibulum sed."