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

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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

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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

“All the cavity nesters; all the nesters that rob the cavity nesters. Everyone is living in there. All of that is lost in one fell swoop. It’s a sort of strip mining.”

From Los Angeles Times ● Oct. 21, 2026

The researchers discovered that some of the brain cells most sensitive to aging were concentrated around the third ventricle, a fluid-filled cavity in the hypothalamus.

From Science Daily ● Oct. 12, 2026

A mass was found in Jake's nose and nasal cavity and he was diagnosed with soft tissue sarcoma.

From BBC ● Oct. 11, 2026

The team then compared the material's superconducting behavior inside and outside the cavity.

From Science Daily ● Oct. 3, 2026

Two great horned owl eggs lie in the cold snow-rimmed cavity in the broken top of the tree.

From "My Side of the Mountain" by Jean Craighead George

Now, researchers led by the University of Michigan have produced compelling evidence that a much simpler approach can stop many cavities from getting worse.

From Science Daily ● Oct. 26, 2026

When Pioneer created samples, cavities intended to hold game accessories didn’t form, came out too thin or didn’t have the required depth.

From The Wall Street Journal ● Sep. 29, 2026

Ventricular expansion refers to enlargement of the fluid-filled cavities within the brain and is considered a sign of poorer brain health.

From Science Daily ● Sep. 2, 2026

They usually nest in cavities that form in large, old trees like oaks.

From BBC ● Aug. 26, 2026

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

From "Finding Junie Kim" by Ellen Oh

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Related Words

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