Definition of bulla in English:



  • 1Medicine
    A bubblelike cavity filled with air or fluid, in particular.

    • ‘Fluid aspirates taken from the bullae revealed gram-positive rods.’
    • ‘A 50-year-old man in the intensive care unit has large bullae bilaterally on his inner thighs.’
    • ‘The bullae are thin-walled and rupture easily, leaving ulcerated skin lesions that heal slowly.’
    • ‘When bullae rupture, a dry, often black eschar may develop.’
    • ‘The lesions are flaccid vesicles or bullae that are initially localized in oral mucosa and later spread randomly to other parts of the body.’
    1. 1.1A large blister containing serous fluid.
      • ‘The bullous form of impetigo presents as a large thin-walled bulla containing serous yellow fluid.’
      • ‘Within three weeks, his toes turned black and serous-filled bullae erupted.’
      • ‘Porphyria cutanea tarda presents with photosensitivity, skin fragility, bruising, and vesicles and bullae that can become hemorrhagic.’
      • ‘It may change colour sequentially from a red-purple to a dusky blue before progressing to necrosis and formation of bullae and eventually becoming haemorrhagic.’
      • ‘Patients with gonococcal infection may have a rash, pustules, or hemorrhagic bullae.’
      bleb, bulla, pustule, vesicle, vesication, blain
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    2. 1.2An abnormal air-filled cavity in the lung.
      • ‘Examination of the surgical specimen revealed a lobe of lung with focal hemorrhage and subpleural bullae.’
      • ‘In the early stages of the disease the alveolar walls appear perfectly normal while in the later stages, fibrosis of the alveolar wall with blebs and bullae is common.’
      • ‘Finding a large, ruptured emphysematous bulla makes resection mandatory.’
      • ‘His chest x ray showed bullae but no collapse, although an emergency computed tomogram confirmed a large, right sided pneumothorax.’
      • ‘Thus, the resection of the bullous area has to be done with care, and the entire lung should be inspected for other blebs or bullae.’
      space, chamber, hollow, hole, pocket, pouch
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  • 2Anatomy
    A rounded prominence.

    • ‘The prootic is a paired bone that forms the anterior lateral face of the auditory bulla.’
    • ‘On the ventral surface of the cranium, the bullae are small, and the paroccipital processes are long and straight.’
    • ‘Directly observable from fossils, the ancestral cetacean also had a pachyostotic bulla and elongate molar shear facets.’
    • ‘The skulls of chinchilla rats have long and narrow rostra, a rounded braincase, enlarged bullae, and delicate zygomatic arches.’
    • ‘The jugular process is enlarged and the tympanic projection is extended anteriorly from the ventral surface of the tympanic bulla.’
    protuberance, projection, swelling, bump, bulge, lump
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  • 3A round seal attached to a papal bull, typically made of lead.

    • ‘‘The discovery is of considerable archaeological interest’, says Pestell. ‘Not only are bullae of this date incredibly rare, so are any seals’.’
    • ‘One venerable conjecture was that it began as a contemptuous reference to papal edicts known as bulls (from the bulla, or seal, appended to the document).’


Latin, literally bubble.