keratinous

IPA/kəˈræt.ɪ.nəs/
IPA/kəˈræt.ə.nəs/

keratinous — adjective

  • keratinouspositive
  • more keratinouscomparative
  • most keratinoussuperlative

1. having a layer of keratin, the tough protein found in hair, nails, feathers, and

1.adjectiveC2
Definition

having a layer of keratin, the tough protein found in hair, nails, feathers, and horns

Example

The bird's beak is covered by a hard keratinous layer.

keratinous layer covering a beak

Doctors removed the keratinous lump from Nila's heel last spring.

keratinous lump in medical context

Common collocations
  • keratinous layer
  • keratinous tissue
  • keratinous growth
  • keratinous sheath
Synonyms
  • cornified

    more technical and often used for skin or cells that have hardened

  • horny

    can overlap in biological writing, but everyday English usually understands it differently

Grammar Patterns

a keratinous layer

keratinous tissue

a keratinous growth

Usage Note

Usually seen in scientific or medical writing before nouns such as layer, tissue, growth, or sheath. In everyday English, writers often choose a plainer phrase like made of keratin instead.

Common Mistakes

The doctor found a keratinous in the skin.
The doctor found a keratinous growth in the skin.
Keratinous is an adjective, so it needs a noun after it.

Word family

  • keratin
    nounC2
  • keratinize
    verbC2
  • keratinization
    nounC2

Synonym discussion

Sense: adjective/1

Keratinous is a technical word used in biology and medicine for tissue or structures that contain keratin or are built from it. Horny can overlap in older scientific writing when the meaning is hard, horn-like tissue, but modern everyday English usually hears a different informal meaning, so it is often avoided outside specialist contexts. Cornified is narrower and usually describes skin or cells that have hardened through keratin formation. Calloused is narrower still, because it refers to skin made thick and hard by rubbing or pressure. A doctor may describe a keratinous lesion, while a non-specialist is more likely to say a hard patch of skin.

horny ↗cornifiedcalloused ↗

Common collocations

Nouns

  • keratinous layer
  • keratinous tissue
  • keratinous growth

Phrases

  • be covered by a keratinous layer
  • remove a keratinous growth

Etymology

GreekModern LatinEnglish

Keratinous comes from keratin with the adjective ending -ous. Keratin entered scientific English through modern scientific language and ultimately goes back to a Greek word meaning horn, which fits the hard material in nails, horns, and similar body parts.