cardiac muscle

noun

Definition of cardiac muscle

: the principal involuntary-muscle tissue of the vertebrate heart made up of striated fibers joined at usually branched ends and functioning in synchronized rhythmic contraction

Recent Examples of cardiac muscle from the Web

The transplant surgeons had clipped some pieces of Astrea’s cardiac muscle.

— New York Times, "Every Cell in Your Body Has the Same DNA. Except It Doesn’t.," 21 May 2018
In the heart, this causes cardiac muscle cells to contract with more force than necessary, for instance.

— beth mole, Ars Technica, "Poison arrows inspire new male contraceptive, scientists report," 21 Jan. 2018
Weird, deadly electrical rhythms arose out of his dying cardiac muscles, like ripples on a stagnating pond, necessitating defibrillating shocks to reset his rhythm.

— siddhartha mukherjee, New York Times, "The Rules of the Doctor’s Heart," 24 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cardiac muscle.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of cardiac muscle

circa 1881

in the meaning defined above

See Words from the same year

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Medical Dictionary

cardiac muscle

noun

medical Definition of cardiac muscle

: the principal muscle tissue of the vertebrate heart that is made up of elongated striated muscle fibers each of which consists of a single cell that has an intrinsic rhythm of contraction and relaxation even when isolated, is joined physically at its often branched ends to other such cells by intercalated disks, and in intact myocardial tissue is synchronized to function in contraction especially by electrical signals of extrinsic origin passing through gap junctions in the intercalated disks — compare smooth muscle, striated muscle