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

Gently scoop out remaining bread, creating a hollow cavity, leaving sides and bottom intact; reserve for dipping. —Kimberly Holland, Southern Living, 6 Nov. 2025

Enamel degradation affects nearly half of the world’s population, contributing to cavities, infections, and even systemic health issues such as diabetes and cardiovascular disease. —Neetika Walter, Interesting Engineering, 5 Nov. 2025

Medullary bone is temporary tissue that forms inside a cavity in long bones of birds and dinosaurs to provide calcium for eggshells, and was previously used in research to identify a pregnant Tyrannosaurus rex in 2016. —Ashley Strickland, CNN Money, 4 Nov. 2025

The door has been hidden inside a cavity in the wall for several years and was designed to slide out across the entrance to the room. —Jack Beresford, MSNBC Newsweek, 4 Nov. 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