smooth muscle

American  

noun

Anatomy.

1. involuntary muscle tissue in the walls of viscera and blood vessels, consisting of nonstriated, spindle-shaped cells.

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smooth muscle British  

noun

1. muscle that is capable of slow rhythmic involuntary contractions: occurs in the walls of the blood vessels, alimentary canal, etc Compare striped muscle

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Etymology

Origin of smooth muscle

First recorded in 1885–90

Example Sentences

PIEZO1 operates primarily within the smooth muscle of the uterus, where it detects rising pressure as contractions strengthen.

From Science Daily • Jan. 13, 2026

These microscopic channels connect neighboring smooth muscle cells so they contract together rather than independently.

From Science Daily • Jan. 13, 2026

During an attack, the smooth muscle surrounding the airways starts to squeeze and tighten, known as bronchoconstriction.

From BBC • Apr. 4, 2024

To construct the protective scaffolding over the potentially deadly plaques, smooth muscle cells that line our blood vessels secrete what is known as "extracellular matrix" -- a fibrous, glue-like material rich in proteins.

From Science Daily • Mar. 11, 2024

The tunica media is composed of intermingled bundles of elastic tissue, smooth muscle fibers, and some fibrous tissue.

From Arteriosclerosis and Hypertension: with Chapters on Blood Pressure, 3rd Edition. by Warfield, Louis Marshall