Definition

Noun: 1. A round lead seal: A disk-shaped seal, historically made of lead, attached to an official papal document (a bull) to authenticate it. 2. A large blister: In medicine, a large, fluid-filled elevation of the skin, typically larger than 1 cm in diameter, containing clear serous fluid.

Usage Examples

• Noun (Historical/Artifact):
  • The ancient papal letter was authenticated by its attached bulla.
  • Museums often display documents with the original bulla still intact.
• Noun (Medical):
  • The dermatologist diagnosed the large, fluid-filled lesion on his arm as a bulla.
  • A severe burn can cause the formation of multiple bullae.

Advanced Usage

• Plural Form: The standard plural is bullae (pronounced /ˈbʊliː/ or /ˈbʊlaɪ/).
• Medical Context: In dermatology, a is specifically distinguished from a smaller blister, which is called a . The plural is commonly used when describing a condition, e.g., "The patient presented with widespread ."

Variants and Related Words

• Bullous (adj): Relating to or characterized by bullae.
  • Bullous pemphigoid is a skin disease that causes large blisters.
• Papal Bull (n): The official document to which a bulla was affixed.

Synonyms

• For the seal: Lead seal, papal seal.
• For the blister: Blister, bleb (though 'bleb' often implies smaller size).

Different Meanings

The two meanings of bulla are entirely distinct and belong to different fields (historical diplomatics/art history and medicine/pathology). Context is essential to determine which meaning is intended.

Noun

1. the round leaden seal affixed to a papal bull
2. (pathology) an elevation of the skin filled with serous fluid