tooth

noun

ˈtüth 

plural teeth ˈtēth 

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 tooth …

—Thomas Gray

4

: taste, liking

5

: a roughness of surface produced by mechanical or artificial means

toothlike

ˈtüth-ˌlīk 

adjective

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

see also in the teeth of, 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

Ancient tooth enamel revealed that early medieval migrants came to England through the Mediterranean and from the Arctic Circle and beyond, according to a new study published in Medieval Archaeology. —Maria Mocerino, Interesting Engineering, 11 Jan. 2026

Although sugar-free gum may help reduce cavities, Fox News Digital has previously reported that dentists warn acids, sweeteners and excessive chewing may harm teeth or trigger other side effects. —Deirdre Bardolf, FOXNews.com, 10 Jan. 2026

But wheels also in motion that could have some legitimate bite, potentially have some teeth from a Heat perspective. —Ira Winderman, Sun Sentinel, 10 Jan. 2026

Camacho gamely snatched one from the water, showing me its extraordinary teeth before releasing it again. —Stanley Stewart, Travel + Leisure, 10 Jan. 2026

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

Phrases Containing tooth

• baby tooth
• cheek tooth
• cut a tooth
• deciduous tooth
• egg tooth
• false saber-tooth cat
• fine-tooth comb
• go over/through (something) with a fine-tooth comb
• hound's-tooth
• long in the tooth
• milk tooth
• permanent tooth
• pivot tooth
• primary tooth
• red in tooth and claw
• saber-tooth cat
• saber-tooth tiger
• spike-tooth harrow
• sweet tooth
• the tooth fairy
• tooth and nail
• tooth fairy
• tooth powder
• tooth shell
• wisdom tooth

Rhymes for tooth

• luth
• muth
• sleuth
• sooth
• youth
• bluetooth
• forsooth
• sawtooth
• tolbooth
• uncouth
• untruth
• vermouth

Kids Definition

tooth

noun

ˈtüth 

plural teeth ˈtēth 

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

-ˌlīk 

adjective

Medical Definition

tooth

noun

ˈtüth 

plural teeth ˈtēth 

: 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