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

• 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

The reactor cavity was full of water. —Prabhat Ranjan Mishra, Interesting Engineering, 24 Oct. 2025

Thus far, 10 have been inspected from a site at the north end of SONGS that holds the canisters in vertical cavities. —Rob Nikolewski, San Diego Union-Tribune, 22 Oct. 2025

Plants to Always Leave Standing The dry stems of certain native perennials offer excellent nesting habitats for around 25% of native bee species that utilize cavity nesting. —Benjamin Vogt, Better Homes & Gardens, 20 Oct. 2025

Her entire stomach had pushed into her chest cavity through an opening in the diaphragm, a muscle that divides the torso, and was wrapped around itself. —Calmatters, Mercury News, 17 Oct. 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