from
The Collaborative International Dictionary of English v.0.48
Bulla \Bul"la\, n.; pl. {Bull[ae]}. [L. bulla bubble. See {Bull}
an edict.]
1. (Med.) A bleb; a vesicle, or an elevation of the cuticle,
containing a transparent watery fluid.
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2. (Anat.) The ovoid prominence below the opening of the ear
in the skulls of many animals; as, the tympanic or
auditory bulla.
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3. A leaden seal for a document; esp. the round leaden seal
attached to the papal bulls, which has on one side a
representation of St. Peter and St. Paul, and on the other
the name of the pope who uses it.
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4. (Zool.) A genus of marine shells. See {Bubble shell}.
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