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

In this resonance, sound excites air trapped within a cavity, creating an airflow imbalance that generates propulsion. — Mrigakshi Dixit, Interesting Engineering, 17 Aug. 2026

The official explained that the damage stems from an old seawall that allows soil underneath the pavers to escape into the river, creating holes and cavities. — Ted Scouten, CBS News, 12 Aug. 2026

Key Takeaways Skipping the rinse after brushing helps fluoride stay on your teeth longer, which may help strengthen enamel and reduce cavities. — Md Published, Verywell Health, 11 Aug. 2026

Leaning that increases year after year, mushrooms or fungal corks growing at the base of your tree, soft soil around the trunk, and bark damage or cavities at the base can all be symptoms of root damage. — Molly Burford, Southern Living, 4 Aug. 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