keratin

ker·a·tin  (kr-tn)

n.

A tough, insoluble protein substance that is the chief structural constituent of hair, nails, horns, and hooves.

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[Greek keras, kert-, horn; see ker-¹ in Indo-European roots + -in.]

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ke·rati·nous (k-rtn-s) adj.

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keratin

Noun

a fibrous protein found in the hair and nails

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keratin  (kr-tn)

Any of a class of tough, fibrous proteins that are the main structural component of hair, nails, horns, feathers, and hooves. Keratins are rich in sulfur-containing amino acids, especially cysteine. Individual keratin molecules are entwined helically around each other in long filaments, which are cross-linked by bonds between sulfur atoms on different chains. The twining and cross-linking produce strength and toughness.

Thesaurus

Noun

1.

keratin - a fibrous scleroprotein that occurs in the outer layer of the skin and in horny tissues such as hair, feathers, nails, and hooves ceratin feather, plumage, plume - the light horny waterproof structure forming the external covering of birds hair - a covering for the body (or parts of it) consisting of a dense growth of threadlike structures (as on the human head); helps to prevent heat loss; "he combed his hair"; "each hair consists of layers of dead keratinized cells" horn - the material (mostly keratin) that covers the horns of ungulates and forms hooves and claws and nails albuminoid, scleroprotein - a simple protein found in horny and cartilaginous tissues and in the lens of the eye