sclerosis

American  

[skli-roh-sis] / sklɪˈroʊ sɪs /

noun

plural

scleroses

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

• sclerosal adjective

Etymology

Origin of sclerosis

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

Example Sentences

Its aging multiple sclerosis franchise continues to suffer losses that must be offset by newer drugs.

From Barron's • Mar. 31, 2026

When Nina Sparks was diagnosed with multiple sclerosis in 2021, she decided very quickly it was going to be the making of her.

From BBC • Mar. 5, 2026

Gunn died Monday at his Toronto home following a battle with amyotrophic lateral sclerosis, or ALS, according to an obituary.

From Los Angeles Times • Mar. 4, 2026

The launch of generic treatments in the U.S. for psoriasis, osteoporosis and multiple sclerosis helped to boost 2025 revenue.

From The Wall Street Journal • Feb. 25, 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