bulla

• ⇰ A bleb; a vesicle, or an elevation of the cuticle, containing a transparent watery fluid.
• ⇰ The ovoid prominence below the opening of the ear in the skulls of many animals; <as>as, the tympanic or auditory <ex>bulla</ex></as>.
• ⇰ 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.
• ⇰ A genus of marine shells. See Bubble shell>.