tooth

noun

plural teeth ˈtēth How to pronounce tooth (audio)
1
a
: one of the hard bony appendages that are borne on the jaws or in many of the lower vertebrates on other bones in the walls of the mouth or pharynx and serve especially for the prehension and mastication of food and as weapons of offense and defense
b
: any of various usually hard and sharp processes especially about the mouth of an invertebrate
2
: a projection resembling or suggesting the tooth of an animal in shape, arrangement, or action
a saw tooth
: such as
a
: any of the regular projections on the circumference or sometimes the face of a wheel that engage with corresponding projections on another wheel especially to transmit force : cog
b
: a small sharp-pointed marginal lobe or process on a plant
3
a
teeth plural : effective means of enforcement
drug laws with teeth
b
: something that injures, tortures, devours, or destroys
jealousy with rankling toothThomas Gray
4
5
: a roughness of surface produced by mechanical or artificial means
toothlike adjective

Illustration of tooth

Illustration of tooth
  • A outside of a molar
  • 1 crown
  • 2 neck
  • 3 roots
  • B cross section of a molar
  • 1 enamel
  • 2 dentin
  • 3 pulp
  • 4 cementum
  • 5 gum
  • C dentition of adult human (upper) D dentition of adult human (lower)
  • 1 incisors
  • 2 canines
  • 3 bicuspids
  • 4 molars
Phrases
in the teeth of
1
: in or into direct contact or collision with
sailing in the teeth of a hurricaneCurrent Biography
2
: in direct opposition to
rule had … been imposed by conquest in the teeth of obstinate resistanceA. J. Toynbee
to the teeth
: fully, completely
armed to the teeth

Examples of tooth in a Sentence

The dentist will have to pull that tooth. You should brush your teeth every morning and night. She clenched her teeth in anger. He has a set of false teeth. the teeth of a saw The labor union showed that it has teeth.
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.
For nearly 80 years, local governments have been adding fluoride to water supplies to prevent tooth decay. Cindy Krischer Goodman, Orlando Sentinel, 3 Mar. 2025 The results revealed that modern shark teeth contain negligible uranium—less than one part per billion—while fossil teeth show significantly higher concentrations, reaching several hundred parts per million. Melissa Cristina Márquez, Forbes, 1 Mar. 2025 However, excessive consumption may lead to negative effects such as tooth enamel erosion, throat irritation, or digestive discomfort. Sohaib Imtiaz, Verywell Health, 1 Mar. 2025 Three sharp teeth emerge from the bottom of its frozen jawline. Jeff Spry, Space.com, 27 Feb. 2025 See All Example Sentences for tooth

Word History

Etymology

Middle English, from Old English tōth; akin to Old High German zand tooth, Latin dent-, dens, Greek odont-, odous

First Known Use

before the 12th century, in the meaning defined at sense 1a

Time Traveler
The first known use of tooth was before the 12th century

Browse Nearby Words

Cite this Entry

“Tooth.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tooth. Accessed 9 Mar. 2025.

Kids Definition

tooth

noun
plural teeth ˈtēth How to pronounce tooth (audio)
1
a
: one of the hard bony structures that are usually located on the jaws of vertebrates and are used for seizing and chewing food and as weapons
b
: any of various usually hard and sharp structures especially around the mouth of an invertebrate
2
a
: something like or suggesting the tooth of an animal in shape, arrangement, or action
the tooth of a saw
b
: one of the projections on the rim of a cogwheel that fit between the projections on another part especially to transmit force : cog
toothless
ˈtüth-ləs
adjective
toothlike adjective

Medical Definition

tooth

noun
plural teeth ˈtēth How to pronounce tooth (audio)
: any of the hard bony appendages that are borne on the jaws and serve especially for the prehension and mastication of food see milk tooth, permanent tooth

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