Definition of cavity
1 : an unfilled space within a mass; especially : a hollowed-out space
2 : an area of decay in a tooth : caries
Examples of cavity in a sentence
Some birds nest in tree cavities.
I had two cavities filled at the dentist's.
Origin and Etymology of cavity
Middle French cavité, from Late Latin cavitas, from Latin cavus
First Known Use: 1541
CAVITY Defined for English Language Learners
Definition of cavity for English Language Learners
: a hole or space inside something
: a hole formed in a tooth by decay
CAVITY Defined for Kids
Definition of cavity for Students
1 : a small hole formed in a tooth by decay
2 : a hollow place <The explosion left a cavity in the ground.>
Seen and Heard
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