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 of cavity

• hole
• dent
• pit
• concavity

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

Small owls like screech owls often sleep in tree cavities or nest boxes, while barn owls live up to their name by seeking out barns and empty buildings. —Brandee Gruener, Southern Living, 13 Mar. 2026

Try using a straw to make a mocktail more lavish and minimize direct contact between ingredients, such as natural sugar or sparkling water, and your teeth, which can help reduce the risk of enamel erosion and cavities. —Cristina Mutchler, Verywell Health, 12 Mar. 2026

That bacteria can then enter a patient’s open cavity, leading to infection. —Judy L. Thomas, Kansas City Star, 10 Mar. 2026

Encouraging your kid to brush their teeth twice a day, with a dab of fluoride toothpaste, will guard against cavities. —Barrie Gillies, Parents, 9 Mar. 2026

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