cavity

American  

[kav-i-tee] / ˈkæv ɪ ti /

noun

• cavities
  plural

1. any hollow place; hollow.

2. Anatomy. a hollow space within the body, an organ, a bone, etc.

3. a hollow space or a pit in a tooth, most commonly produced by caries. A cavity may be artificially made to support dental restorations.

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cavity British  

/ ˈkævɪtɪ /

noun

1. a hollow space; hole

2. dentistry a soft decayed area on a tooth See caries

3. any empty or hollow space within the body

   the oral cavity

4. electronics See cavity resonator

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cavity Scientific  

/ kăv′ĭ-tē /

1. A hollow; a hole.

2. A hollow area within the body.

3. A pitted area in a tooth caused by caries.

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Usage

What is a cavity? A cavity is a pit or hole in a tooth caused by the decay of the enamel and bone, such as you might get if you don’t brush your teeth regularly. A cavity is more generally any hollow place or crater, as in When the old building was torn down, all that was left was a huge cavity in the ground. A cavity is also any other hole, divet, or pit in the body, such as the spinal cavity, which surrounds your spinal cord. Example: That cavity in your molar is probably from all the soda you drink.

Synonym Usage

See hole.

Other Word Forms

Derived Forms

• subcavity
  noun
• cavitied
  adjective
• uncavitied
  adjective

Inflected Forms

Nouns

• cavities
  plural

Etymology

Origin of cavity

First recorded in 1535–45; from Middle French cavite from Late Latin cavitās “hollowness,” equivalent to Latin cav(us) “hollow” + -itās -ity

Explanation

A cavity is a carved-out space inside something solid like a wall or a tooth. If you have a cavity, you have a hole in your tooth, and it’s time to go to the dentist for a filling. Lucky you. Doctors sometimes refer to various internal body parts as cavities, such as the "abdominal cavity," which includes the stomach and other hollow parts of the abdomen. You are more likely to hear the word at the dentist’s office, when she finds a cavity, which is a space in your tooth that's been eaten away by decay. Fun! (Not.) Cavity shares the Latin root cavus, "hollow," with the word cave.

Example Sentences

See Examples For:

cavity cavities

Among its advances is a structure known as a phononic cavity, which traps mechanical vibrations so they can interact more strongly with the electron spin inside a qubit.

From Science Daily ● Sep. 12, 2026

"The Earth-ionosphere cavity acts as a natural resonator that amplifies electromagnetic waves right around the mass range we wanted to probe."

From Science Daily ● Sep. 6, 2026

As immune cells entered the treated area, new blood vessels also formed throughout the stroke cavity.

From Science Daily ● Sep. 4, 2026

A surveyor's report commissioned by shared-ownership provider, Sage Homes, found evidence the walls may have been wet when plasterboard was installed, and also identified issues with insulation and debris in the cavity walls.

From BBC ● Sep. 4, 2026

By the time a carcass reached my spot on the line, the fluids had mostly drained out, everything except for dense clots of blood in the neck and upper chest cavity.

From "The Things They Carried" by Tim O'Brien

Those techniques do not work particularly well for qubits placed inside phononic cavities.

From Science Daily ● Sep. 12, 2026

She shared that her cancer had spread to her peritoneum, a membrane that lines the abdominal and pelvic cavities and protects internal organs.

From BBC ● Aug. 6, 2026

This field, known as nanocell engineering, seeks to create cell-like structures with specialized surfaces and internal pores or cavities.

From Science Daily ● Aug. 6, 2026

After brain tumors are removed, a surgeon uses the tiles to line the walls of the empty cavities.

From The Wall Street Journal ● May 30, 2026

“Getting seven teeth drilled for cavities made me never want to eat candy again!”

From "Finding Junie Kim" by Ellen Oh

Related Words

• crater