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, synthetic blastoids develop a blastocoel cavity and the three main cell types (epiblast, trophectoderm, and primitive endoderm) within one week, just like natural blastocysts. —Srishti Gupta, Interesting Engineering, 28 Mar. 2026

Tomar said stripping fluoride from the water in Birmingham has unnecessarily put residents at greater risk for cavities. —Aria Bendix, NBC news, 27 Mar. 2026

The International Forum of Allergy & Rhinology published a study which examined data from many users of an acoustic therapy device to discover that nasal cavity dimensions affected treatment needs for congestion. —Matthew Kayser, USA Today, 25 Mar. 2026

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