See more synonyms for muscle on
  1. a tissue composed of cells or fibers, the contraction of which produces movement in the body.
  2. an organ, composed of muscle tissue, that contracts to produce a particular movement.
  3. muscular strength; brawn: It will take a great deal of muscle to move this box.
  4. power or force, especially of a coercive nature: They put muscle into their policy and sent the marines.
  5. lean meat.
  6. Slang.
    1. a hired thug or thugs.
    2. a bodyguard or bodyguards: a gangster protected by muscle.
  7. a necessary or fundamental thing, quality, etc.: The editor cut the muscle from the article.
verb (used with object), mus·cled, mus·cling.
  1. Informal. to force or compel others to make way for: He muscled his way into the conversation.
  2. to make more muscular: The dancing lessons muscled her legs.
  3. to strengthen or toughen; put muscle into.
  4. Informal. to accomplish by muscular force: to muscle the partition into place.
  5. Informal. to force or compel, as by threats, promises, influence, or the like: to muscle a bill through Congress.
verb (used without object), mus·cled, mus·cling.
  1. Informal. to make one's way by force or fraud (often followed by in or into).
  1. Informal. (of a machine, engine, or vehicle) being very powerful or capable of high-speed performance: a muscle power saw.

Origin of muscle

1525–35; < Latin mūsculus literally, little mouse (from fancied resemblance to some muscles), equivalent to mūs mouse + -culus -cle1
Related formsmus·cle·less, adjectivemus·cly, adjectiveo·ver·mus·cled, adjectivetrans·mus·cle, nounun·mus·cled, adjective

Synonyms for muscle

See more synonyms for on Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for muscle

Contemporary Examples of muscle

Historical Examples of muscle

  • In a swerve he almost stopped, every muscle of his big body trembling in affright.


    W. A. Fraser

  • The tall son of Hanover was lean of flesh, but gross in muscle.


    W. A. Fraser

  • "Ah, but he has mind as well as muscle," put in Mr. Stewart.

    In the Valley

    Harold Frederic

  • There was some tension of mind or muscle that kept sleep far from him.

    The Rock of Chickamauga

    Joseph A. Altsheler

  • She came up straight and tall, a concluded resolution in every muscle.

    Tiverton Tales

    Alice Brown

British Dictionary definitions for muscle


  1. a tissue composed of bundles of elongated cells capable of contraction and relaxation to produce movement in an organ or part
  2. an organ composed of muscle tissue
  3. strength or force
  1. (intr; often foll by in, on, etc) informal to force one's way (in)
Derived Formsmuscly, adjective

Word Origin for muscle

C16: from medical Latin musculus little mouse, from the imagined resemblance of some muscles to mice, from Latin mūs mouse
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for muscle

late 14c., from Middle French muscle "muscle, sinew" (14c.) and directly from Latin musculus "a muscle," literally "little mouse," diminutive of mus "mouse" (see mouse (n.)).

So called because the shape and movement of some muscles (notably biceps) were thought to resemble mice. The analogy was made in Greek, too, where mys is both "mouse" and "muscle," and its comb. form gives the medical prefix myo-. Cf. also Old Church Slavonic mysi "mouse," mysica "arm;" German Maus "mouse; muscle," Arabic 'adalah "muscle," 'adal "field mouse." In Middle English, lacerte, from the Latin word for "lizard," also was used as a word for a muscle.

Musclez & lacertez bene one selfe þing, Bot þe muscle is said to þe fourme of mouse & lacert to þe fourme of a lizard. [Guy de Chauliac, "Grande Chirurgie," c.1425]

Hence muscular and mousy are relatives, and a Middle English word for "muscular" was lacertous, "lizardy." Figurative sense of "force, violence, threat of violence" is 1930, American English. Muscle car "hot rod" is from 1969.


1913, "to accomplish by strength," from muscle (n.). Related: Muscled; muscling. To muscle in is 1929 in underworld slang.

Online Etymology Dictionary, © 2010 Douglas Harper

muscle in Medicine


  1. A tissue consisting predominantly of contractile cells and classified as skeletal, cardiac, or smooth, the last lacking transverse striations characteristic of the first two.
  2. Any of the contractile organs of the body by which movements of the various organs and parts are effected, and whose fibers are usually attached at each extremity to a bone or other structure by a tendon.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

muscle in Science


  1. A body tissue composed of sheets or bundles of cells that contract to produce movement or increase tension. Muscle cells contain filaments made of the proteins actin and myosin, which lie parallel to each other. When a muscle is signaled to contract, the actin and myosin filaments slide past each other in an overlapping pattern.Skeletal muscle effects voluntary movement and is made up of bundles of elongated cells (muscle fibers), each of which contains many nuclei.Smooth muscle provides the contractile force for the internal organs and is controlled by the autonomic nervous system. Smooth muscle cells are spindle-shaped and each contains a single nucleus.Cardiac muscle makes up the muscle of the heart and consists of a meshwork of striated cells.
Related formsmuscular adjective
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Idioms and Phrases with muscle


In addition to the idiom beginning with muscle

  • muscle in

also see:

  • flex one's muscles
  • move a muscle
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.