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noun \ˈtüth\

Simple Definition of tooth

  • : one of the hard white objects inside the mouth that are used for biting and chewing

  • : a sharp or pointed object that sticks out of something and is part of a row of similar objects

  • teeth : the power that makes something effective

Source: Merriam-Webster's Learner's Dictionary

Full Definition of tooth



play \ˈtēth\
  1. 1a :  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 defenseb :  any of various usually hard and sharp processes especially about the mouth of an invertebrate

  2. 2 :  taste, liking

  3. 3 :  a projection resembling or suggesting the tooth of an animal in shape, arrangement, or action <a saw tooth>: asa :  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 :  cogb :  a small sharp-pointed marginal lobe or process on a plant

  4. 4a :  something that injures, tortures, devours, or destroys <jealousy with rankling tooth — Thomas Gray>b plural :  effective means of enforcement <drug laws with teeth>

  5. 5 :  a roughness of surface produced by mechanical or artificial means


play \ˈtüth-ˌlīk\ adjective

in the teeth of

  1. 1 :  in or into direct contact or collision with <sailing in the teeth of a hurricane — Current Biography>

  2. 2 :  in direct opposition to <rule had…been imposed by conquest in the teeth of obstinate resistance — A. J. Toynbee>

to the teeth

  1. :  fully, completely <armed to the teeth>

Examples of tooth in a sentence

  1. The dentist will have to pull that tooth.

  2. You should brush your teeth every morning and night.

  3. She clenched her teeth in anger.

  4. He has a set of false teeth.

  5. the teeth of a saw

  6. The labor union showed that it has teeth.

Illustration of tooth

Origin and Etymology of tooth

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

First Known Use: before 12th century

Rhymes with tooth

TOOTH Defined for Kids


noun \ˈtüth\

Definition of tooth for Students



  1. 1 :  one of the hard bony structures set in sockets on the jaws of most vertebrates and used especially to chew and bite

  2. 2 :  something like or suggesting an animal's tooth in shape, arrangement, or action <the teeth of a comb>

  3. 3 :  one of the projections around the rim of a wheel that fit between the projections on another part causing the other part to move as the wheel turns


\ˈtüth-ləs\ adjective

Medical Dictionary


noun \ˈtüth\

Medical Definition of tooth



  1. :  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

Illustration of tooth

Learn More about tooth

Seen and Heard

What made you want to look up tooth? Please tell us where you read or heard it (including the quote, if possible).


to proceed clumsily or ineffectually

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