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

Dim light will make the cavity’s dimensions impossible to read. —Rebecca Mead, New Yorker, 9 Feb. 2026

For instance, studying subsurface cavities is a primary goal of an instrument called the Subsurface Radar Sounder, or SRS, planned for the EnVision mission being developed by the European Space Agency, which can penetrate the planet's surface to depths of several hundred meters. —Sharmila Kuthunur, Space.com, 9 Feb. 2026

The training also makes clear that the definition of ectopic pregnancies — which are always life-threatening — includes any that implant in an abnormal location outside of the uterine cavity. —Cassandra Jaramillo, CNN Money, 9 Feb. 2026

Prescott noted that no body or cavity search was conducted. —Justin Muszynski, Hartford Courant, 7 Feb. 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