sclerosis

American  

[skli-roh-sis] / sklɪˈroʊ sɪs /

noun

• scleroses
  plural

1. Pathology. a hardening or induration of a tissue or part, or an increase of connective tissue or the like at the expense of more active tissue.

2. Botany. a hardening of a tissue or cell wall by thickening or lignification.

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sclerosis British  

/ sklɪəˈrəʊsɪs /

noun

1. pathol a hardening or thickening of organs, tissues, or vessels from chronic inflammation, abnormal growth of fibrous tissue, or degeneration of the myelin sheath of nerve fibres, or (esp on the inner walls of arteries) deposition of fatty plaques Compare arteriosclerosis atherosclerosis multiple sclerosis

2. the hardening of a plant cell wall or tissue by the deposition of lignin

3. a debilitating lack of progress or innovation within an institution or organization

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Other Word Forms

Derived Forms

• sclerosal
  adjective

Inflected Forms

Nouns

• scleroses
  plural

Etymology

Origin of sclerosis

1350–1400; Middle English < Medieval Latin < Greek sklḗrōsis hardening. See scler-, -osis

Explanation

Someone is diagnosed with the condition sclerosis when a part of their body becomes unusually hardened. A diet that's too high in cholesterol can cause sclerosis of the arteries. In many cases of sclerosis, the stiffening of tissue in organs, nerves, or arteries happens when it's gradually replaced with harder connective tissue. One of the most common forms of sclerosis is called multiple sclerosis, or MS. In this disorder, nerve cells in the spinal cord and brain are affected. Eventually patients with multiple sclerosis experience lack of coordination, numbness, and other symptoms. The Greek root is skleros, or "hard."

Example Sentences

See Examples For:

sclerosis

Despite the brain tumour and a recent diagnosis of multiple sclerosis, Oli was otherwise fit and well and positive about his future.

From BBC ● Sep. 8, 2026

For Novartis, recent positive results from a separate multiple sclerosis study should make the failure of the pelacarsen trial more palatable for investors, Jefferies said.

From The Wall Street Journal ● Sep. 7, 2026

Novartis is studying its therapy rap-cel in eight autoimmune trials, including in multiple sclerosis and rheumatoid arthritis—a broad bet that has enrolled more than 500 patients.

From The Wall Street Journal ● Sep. 3, 2026

Novartis was testing rap-cel in lupus, multiple sclerosis and other autoimmune diseases.

From The Wall Street Journal ● Sep. 1, 2026

Yolanda is the day worker who takes care of Mrs. Farkas who has multiple sclerosis and who lives across the street from the Zamborskas on Tower Hill Road.

From "Silent To The Bone" by E.L. Konigsburg