\ˈtüth \
plural teeth\ˈtēth \

Definition of tooth 

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 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

3a teeth plural : effective means of enforcement drug laws with teeth

b : something that injures, tortures, devours, or destroys jealousy with rankling tooth— Thomas Gray

4 : taste, liking

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

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 resistance— A. J. Toynbee

to the teeth

: fully, completely armed to the teeth

Illustration of tooth

Illustration of tooth

tooth 1a: 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

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Other Words from tooth

toothlike \ˈtüth-​ˌlīk \ adjective

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.
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Recent Examples on the Web

There are no teeth inside the digestive tract past the mouth. Joe Graedonteresa Graedon, The Seattle Times, "Food go down the wrong tube? Try sipping cola," 28 Nov. 2018 Researchers discovered starch granules in the tooth plaque of some of the foragers. Mark Barna, Discover Magazine, "When Farmers and Foragers First Met," 24 Oct. 2018 Instead of covering your whole face with its internal anatomy, try just a quarter of it by outlining your jawbone, teeth and eye socket with fluorescent hues. 24. Devon Abelman, Allure, "27 Last-Minute Halloween Costumes You Can Do With Just Makeup," 10 Oct. 2018 Saliva is responsible for cleaning out food particles and protecting the teeth and gums from bacterial infection, says Alice Boghosian, spokesperson for the American Dental Association. Samantha Lefave, Redbook, "Why You Should Never Ignore Sweet-Smelling Urine (or These Other Body Odors)," 3 Aug. 2018 With highlighter, draw tall rectangle mouth, teeth and smile lines on butternut squash. Woman's Day Staff, Woman's Day, "50+ Creative Pumpkin Carving Ideas for Halloween," 25 July 2018 There’s more: In 2017, the same officer knocked out a tooth of a 14-year-old student, Q.W., according to the lawsuit and news reports at the time. Anne Branigin, The Root, "High School Antwon Rose Attended Faces Brutal Allegations of Police Abuse: Report," 28 June 2018 With gibbon remains in Asia primarily limited to teeth and small bone fragments, the fossil record for these beasts is far from complete. National Geographic, "Ancient Royal Tomb Yields Strange New Ape Species," 21 June 2018 Goodman, whose sister is none other than Vogue’s very own editor extraordinaire Tonne Goodman, actually cut her teeth under Anna Wintour, who was then at Harper’s Bazaar. Lilah Ramzi, Vogue, "In Her New Book, Wendy Goodman Asks May I Come In? Thankfully, a Lot of People Said Yes," 4 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tooth.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tooth

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

History and Etymology for tooth

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

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Statistics for tooth

Last Updated

9 Dec 2018

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Time Traveler for tooth

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

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More Definitions for tooth



English Language Learners 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


\ˈtüth \
plural teeth\ˈtēth \

Kids Definition of tooth

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

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

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

Other Words from tooth

toothless \ˈtüth-​ləs \ adjective


\ˈtüth \
plural teeth\ˈtēth \

Medical Definition of tooth 

: 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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More from Merriam-Webster on tooth

Rhyming Dictionary: Words that rhyme with tooth

Spanish Central: Translation of tooth

Nglish: Translation of tooth for Spanish Speakers

Britannica English: Translation of tooth for Arabic Speakers Encyclopedia article about tooth

Comments on tooth

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