cavity

noun

cav·​i·​ty ˈka-və-tē 

plural cavities

1

: an unfilled space within a mass

especially : a hollowed-out space

2

: an area of decay in a tooth : caries

Synonyms

• concavity
• dent
• depression
• dint
• hole
• hollow
• indentation
• indenture
• pit
• recess

Examples of cavity in a Sentence

Some birds nest in tree cavities.

I had two cavities filled at the dentist's.

Recent Examples on the Web

The bill passed on April 29 in the middle of Miami-Dade’s own fight over fluoridation of tap water, which the county has been doing since the 1950s as a way to reduce cavities and other dental issues. —Douglas Hanks, Miami Herald, 7 May 2025

And a city in Canada recently voted to add fluoride back into the drinking water after seeing that local second-graders had significantly higher rates of cavities than those in a neighboring city that fluoridated its water. —Deidre McPhillips, CNN Money, 7 May 2025

There is no evidence that properly maintained levels of fluoride in drinking water provide anything but benefits through the reduction of dental cavities. —Scott A. Rivkees, Time, 6 May 2025

The bone had thick walls and a narrower bone marrow cavity. —Margherita Bassi, Smithsonian Magazine, 1 May 2025

Word History

Etymology

borrowed from Middle French & Late Latin; Middle French cavité, borrowed from Late Latin cavitāt-, cavitās, from Latin cavus "hollow, concave" + -itāt-, -itās -ity — more at hole entry 1

First Known Use

1541, in the meaning defined at sense 1

Phrases Containing cavity

• abdominal cavity
• body cavity
• pelvic cavity
• segmentation cavity
• spinal cavity
• thoracic cavity

Rhymes for cavity

• gravity
• concavity
• depravity
• intracavity
• microgravity
• supergravity

Kids Definition

cavity

noun

cav·​i·​ty ˈkav-ət-ē 

plural cavities

1

: a hollow place

especially : an unfilled bodily space

lung cavity

2

: a hole hollowed out in a tooth by decay

Medical Definition

cavity

noun

cav·​i·​ty ˈkav-ət-ē 

plural cavities

1

: an unfilled space within a mass

2

: an area of decay in a tooth : caries