toothtop: cross section of a human toothbottom: teeth on mechanical gearstooth (to?oth)n. pl. teeth (t?th) 1. a. One of a set of hard, bonelike structures in the mouths of vertebrates, usually attached to the jaw or rooted in sockets and typically composed of a core of soft pulp surrounded by a layer of hard dentin that is coated with cementum or enamel at the crown and used for biting or chewing food or as a means of attack or defense.b. A similar hard projection in an invertebrate, such as one of a set of projections on the hinge of a bivalve or on the radula of a snail.2. A projecting part resembling a tooth in shape or function, as on a comb, gear, or saw.3. A small, notched projection along a margin, especially of a leaf. Also called dent2.4. A rough surface, as of paper or metal.5. a. often teeth Something that injures or destroys with force: the teeth of the blizzard.b. teeth Effective means of enforcement; muscle: “This … puts real teeth into something where there has been only lip service” (Ellen Convisser).v. (to?oth, to?oth) toothed, tooth·ing, tooths v.tr.1. To furnish (a tool, for example) with teeth.2. To make a jagged edge on.v.intr. To become interlocked; mesh.Idioms: get/sink (one’s) teeth into Slang To be actively involved in; get a firm grasp of. show/bare (one’s) teeth To express a readiness to fight; threaten defiantly. to the teeth Lacking nothing; completely: armed to the teeth; dressed to the teeth.[Middle English toth, from Old English t?th; see dent- in Indo-European roots.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.tooth (tu??) n, pl teeth (ti??) 1. (Dentistry) any of various bonelike structures set in the jaws of most vertebrates and modified, according to the species, for biting, tearing, or chewing. 2. (Zoology) any of various similar structures in invertebrates, occurring in the mouth or alimentary canal3. anything resembling a tooth in shape, prominence, or function: the tooth of a comb. 4. (Botany) any of the various small indentations occurring on the margin of a leaf, petal, etc5. (Mechanical Engineering) any one of a number of uniform projections on a gear, sprocket, rack, etc, by which drive is transmitted6. taste or appetite (esp in the phrase sweet tooth)7. long in the tooth old or ageing: used originally of horses, because their gums recede with age8. tooth and nail with ferocity and force: we fought tooth and nail. vb9. (tr) to provide with a tooth or teeth10. (Mechanical Engineering) (intr) (of two gearwheels) to engage[Old English t?th; related to Old Saxon tand, Old High German zand, Old Norse tonn, Gothic tunthus, Latin dens] ?toothless adj ?tooth?like adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014tooth (tu?) n., pl. teeth, (?tu ???, -ð??) n. 1. (in most vertebrates) one of the hard bodies or processes usu. attached in a row to each jaw, serving for the prehension and mastication of food, as weapons of attack or defense, etc., and in mammals typically composed chiefly of dentin surrounding a sensitive pulp and covered on the crown with enamel. 2. (in invertebrates) any of various similar or analogous processes occurring in the mouth or alimentary canal, or on a shell. 3. any projection resembling a tooth. 4. one of the projections of a comb, rake, saw, etc. 5. a. any of the uniform projections on a gear or rack by which it drives or is driven by a gear, rack, or worm. b. any of the uniform projections on a sprocket by which it drives or is driven by a chain. 6. Bot. any small, toothlike marginal lobe. 7. a sharp, distressing, or destructive attribute or agency. 8. taste, relish, or liking. 9. teeth, effective power, esp. to enforce or accomplish something: to put teeth into a law. 10. a roughened surface, as on a sharpening stone, grinding wheel, or drawing paper. v.t. 11. to furnish with teeth. v.i. 12. to interlock, as cogwheels. Idioms: 1. in the teeth of, straight into, against, or in defiance of. 2. long in the tooth, noticeably old; elderly. 3. set one’s teeth, to become resolute; prepare for difficulty. 4. show one’s teeth, to become menacing; reveal one’s hostility. 5. to the teeth, to the fullest extent; fully; entirely: armed to the teeth. [before 900; Middle English; Old English t?th, c. Old Frisian t?th, Old Saxon tand, Old High German zan(t), Old Norse t?nn; akin to Gothic tunthus, Latin d?ns, Greek odoús, Skt dánta] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.tootha full set of adult human teethtooth (to?oth) Plural teeth (t?th) 1. Any of the hard bony structures in the mouth used to grasp and chew food and as weapons of attack and defense. In mammals and many other vertebrates, the teeth are set in sockets in the jaw. In fish and amphibians, they grow in and around the palate. See also dentition.2. A similar structure in certain invertebrate animals.The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.toothPast participle: toothedGerund: toothingImperativePresentPreteritePresent ContinuousPresent PerfectPast ContinuousPast PerfectFutureFuture PerfectFuture ContinuousPresent Perfect ContinuousFuture Perfect ContinuousPast Perfect ContinuousConditionalPast ConditionalImperativetoothtoothPresentI toothyou toothhe/she/it toothswe toothyou tooththey toothPreteriteI toothedyou toothedhe/she/it toothedwe toothedyou toothedthey toothedPresent ContinuousI am toothingyou are toothinghe/she/it is toothingwe are toothingyou are toothingthey are toothingPresent PerfectI have toothedyou have toothedhe/she/it has toothedwe have toothedyou have toothedthey have toothedPast ContinuousI was toothingyou were toothinghe/she/it was toothingwe were toothingyou were toothingthey were toothingPast PerfectI had toothedyou had toothedhe/she/it had toothedwe had toothedyou had toothedthey had toothedFutureI will toothyou will toothhe/she/it will toothwe will toothyou will tooththey will toothFuture PerfectI will have toothedyou will have toothedhe/she/it will have toothedwe will have toothedyou will have toothedthey will have toothedFuture ContinuousI will be toothingyou will be toothinghe/she/it will be toothingwe will be toothingyou will be toothingthey will be toothingPresent Perfect ContinuousI have been toothingyou have been toothinghe/she/it has been toothingwe have been toothingyou have been toothingthey have been toothingFuture Perfect ContinuousI will have been toothingyou will have been toothinghe/she/it will have been toothingwe will have been toothingyou will have been toothingthey will have been toothingPast Perfect ContinuousI had been toothingyou had been toothinghe/she/it had been toothingwe had been toothingyou had been toothingthey had been toothingConditionalI would toothyou would toothhe/she/it would toothwe would toothyou would tooththey would toothPast ConditionalI would have toothedyou would have toothedhe/she/it would have toothedwe would have toothedyou would have toothedthey would have toothedCollins English Verb Tables © HarperCollins Publishers 2011