Definition of: tooth

(tth) noun plural teeth (tēth)
1. One of the hard, dense structures in the mouth of a vertebrate, used for seizing and chewing food, as offensive and defensive weapons, etc. It consists chiefly of dentine or ivory, invested on the outer surface and crown with enamel, and a root embedded in the gum, with a small opening leading into a pulp cavity richly supplied with blood vessels and nerves. ♦ Collateral adjective: dental.
2. One of various hard calcareous or chitinous bodies of the oral or gastric regions of invertebrates.
3. Any one of various small toothlike projections.
4. Zool. A process near the hinge of a bivalve shell.
5. Bot. One of the processes in the peristome of a moss.
6. Something resembling a tooth in form or use; specifically, a projecting point, pin, tine, or cog, as on a saw, comb, fork, rake, or gearwheel.
7. Appetite, liking, or taste (for something): She has a sweet tooth.
8. plural That part which opposes, as in the gnawing, biting, or piercing manner of a tooth; the face of opposition, especially when involving resistance or risk: the teeth of the wind; He disobeyed them in their teeth.
9. plural Means of enforcement: to put teeth into a law.
10. In paper or painting grounds, coarseness; irregularity of surface.
—armed to the teeth Completely or heavily armed.
—by the skin of one's teeth Barely; by the narrowest possible margin.
—in the teeth of Directly against, counter to, or in defiance of.
—to put teeth into To provide (something) with strength or power.
—to show one's teeth To display a disposition to fight; threaten.
—to throw (or cast) in one's teeth To fling at one, as a challenge or taunt.
—v.t.
1. To supply with teeth, as a rake or saw.
2. To give a serrated edge to; indent.
—v.i.
3. To become interlocked, as gearwheels; to gear. [<ON tōth, tōdh]
TEETH OF HUMAN ADULT
A. Cross–section of a molar.
B. Left upper jaw.
C. Left lower jaw.
A. a. Crown. b. Enamel. c. Pulp cavity. d. Dentine. e. Cement. ƒ. Roots.
B. & C. g. Incisors. h. Canines. i. Bicuspids. j. Molars. k. Wisdom teeth.