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

That bacteria can then enter a patient’s open cavity, leading to infection. —Judy L. Thomas, Kansas City Star, 20 Apr. 2026

Install Multiple Houses Different species of native bees use nesting cavities of different sizes. —Lauren Landers, Better Homes & Gardens, 20 Apr. 2026

When Robby scissors through the uterus, a perfect flood of bloody fluid comes cascading outward, immediately filling the prosthetic belly’s cavity. —Kathryn Vanarendonk, Vulture, 17 Apr. 2026

Many communities have chosen to add fluoride to the tap water for decades, as a public health measure that is estimated to reduce cavities by around 25%. —Pien Huang, NPR, 15 Apr. 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