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

For example, a small cavity that needs a quick filling might cost $200. —Blake Farmer, Miami Herald, 24 Mar. 2026

As disease kills off neurons, the brain shrinks, and the space in the middle cavity enlarges. —Anderson Cooper, CBS News, 22 Mar. 2026

To keep them plentiful, the FWC recommends homeowners preserve trees with cavities or peeling bark, leave dead fronds on palm trees to provide roosting spots, add native plants when landscaping to attract pollinators and install a bat house on your property. —Lois K. Solomon, Sun Sentinel, 21 Mar. 2026

Conventional atomic clocks rely on microwave cavity resonance, in which microwaves interact with atoms in a resonant chamber to produce a stable frequency. —Jijo Malayil, Interesting Engineering, 19 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