Definitions
1.nounA blister, vesicle, or other thin-walled cavity or lesion.
2.nounA clay envelope or hollow ball, typically with seal impressions or writing on its outside indicating its contents.
3.nounIn ancient Rome, a kind of amulet or boss.
4.nounLater, a handwritten document from the papal chancellery.
5.nounThe tympanic part of a temporal bone (having a bubble-like appearance)