bulla

Etymology 1

Borrowed from Latin bulla (“bubble”). Doublet of bull.

noun

1. (biology, medicine) A blister, vesicle, or other thin-walled cavity or lesion, as:
   1. (biology, medicine) (usually and especially) Such a blister that is more than 5 mm in diameter.
2. (archaeology) A clay envelope or hollow ball, typically with seal impressions or writing on its outside indicating its contents.
3. (historical) In ancient Rome, a kind of amulet or boss.
4. Later, a handwritten document from the papal chancellery.
5. The tympanic part of a temporal bone (having a bubble-like appearance)

Etymology 2

noun

1. A rich Jamaican cake made with molasses and spiced with ginger and nutmeg.