cavity
Americannoun
-
cavities
plural
-
any hollow place; hollow.
-
Anatomy. a hollow space within the body, an organ, a bone, etc.
-
a hollow space or a pit in a tooth, most commonly produced by caries. A cavity may be artificially made to support dental restorations.
noun
-
a hollow space; hole
-
dentistry a soft decayed area on a tooth See caries
-
any empty or hollow space within the body
the oral cavity
-
electronics See cavity resonator
-
A hollow; a hole.
-
A hollow area within the body.
-
A pitted area in a tooth caused by caries.
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
Inflected Forms
Nouns
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.
Vocabulary lists containing cavity
There's No There There: Synonyms for "Empty"
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Sounder
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
And Then, Boom!
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
“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
Unlike fat that accumulates directly beneath the skin, visceral fat lies deep within the abdominal cavity, surrounding organs such as the liver and intestines.
From Science Daily ● Oct. 11, 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
This created a coupled system in which the superconducting material interacted with the specially engineered electromagnetic environment inside the cavity.
From Science Daily ● Oct. 3, 2026
It was a fairly straightforward calculation: how much light does an empty cavity radiate?
From "Zero: The Biography of a Dangerous Idea" by Charles Seife
![]()
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
Because the protection comes from a continuous mechanical field that is compatible with phononic cavities, the technique could operate inside the same structures that may eventually connect stationary nodes in quantum networks.
From Science Daily ● Sep. 12, 2026
Those techniques do not work particularly well for qubits placed inside phononic cavities.
From Science Daily ● Sep. 12, 2026
They usually nest in cavities that form in large, old trees like oaks.
From BBC ● Aug. 26, 2026
An onrushing sense of claustrophobia stifled him, compressed his lungs, as if water filled their cavities.
From "The Maze Runner" by James Dashner
![]()
Random Word
Spin the wheel and learn a new word!
Get a wordDefinitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.