cavity

noun

cav·​i·​ty ˈka-və-tē How to pronounce cavity (audio)
plural cavities
Synonyms of cavitynext
1
: an unfilled space within a mass
especially : a hollowed-out space
2
: an area of decay in a tooth : caries

Synonyms of cavity

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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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The new technology instead places the diamond directly inside a laser cavity. — Georgina Jedikovska, Interesting Engineering, 22 Oct. 2026 Will Brantley, president of the Georgia Academy of Pediatric Dentistry, said sticky and chewy candies tend to cling to teeth, leaving behind sugary residue that can contribute to cavities. — Nancy Badertscher, AJC.com, 21 Oct. 2026 About 1 in 5 adults ages 20 to 64 has at least one untreated cavity, and nearly all adults 65 and older have dealt with tooth decay at some point, according to the Centers for Disease Control and Prevention. — Ryan Brennan, Sacbee.com, 20 Oct. 2026 About 1 in 5 adults ages 20 to 64 has at least one untreated cavity, and nearly all adults 65 and older have had tooth decay at some point, according to the Centers for Disease Control and Prevention. — Ryan Brennan, Miami Herald, 20 Oct. 2026 See All Example Sentences for cavity

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

Time Traveler
The first known use of cavity was in 1541

Phrases Containing cavity

Rhymes for cavity

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Browse Nearby Words

cavitoma
cavity
cavity oscillator
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Cite this Entry

“Cavity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cavity. Accessed 27 Oct. 2026.

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Kids Definition

cavity

noun
cav·​i·​ty ˈkav-ət-ē How to pronounce cavity (audio)
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 How to pronounce cavity (audio)
plural cavities
1
: an unfilled space within a mass
2
: an area of decay in a tooth : caries

More from Merriam-Webster on cavity

Britannica.com: Encyclopedia article about cavity

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