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

But the main cause of sclerosis in the U.S. defense industrial base is the Pentagon spending drawdown after the Cold War.

From The Wall Street Journal ● Jul. 20, 2026

Sir Stephen met a group of disabled people at an event to discuss the findings of his review at the MS Society, a charity that supports people affected by multiple sclerosis.

From BBC ● Jul. 8, 2026

In patients with multiple sclerosis, Roche is running a Phase 1 study to protect brain cells with a BrainShuttle-enhanced version of the CD20 antibody.

From Barron's ● Jun. 3, 2026

Jenny Slatten, 68, who married Sumit Singh, 38, in Season 1 of TLC’s ‘90-Day Fiancé: The Other Side,’ has been diagnosed with ALS, amyotrophic lateral sclerosis.

From Los Angeles Times ● May 27, 2026

He lived his life in defiance of that very prospect, assiduously looking after our car, paying the bills on time, never discussing his advancing multiple sclerosis nor missing a day of work.

From "Becoming" by Michelle Obama