muscle

1. (uncountable) A contractile form of tissue which animals use to effect movement.Examples: "Muscle consists largely of actin and myosin filaments."; "For as the Trunk of the Body, is kept from tilting forvvard by the Muſcules of the Back: So, from falling backvvard, by theſe of the Belly."Synonyms: thewuncountable

2. (countable) An organ composed of muscle tissue.Examples: "His brow and hair and the palms of his hands were wet, and there was a kind of nervous contraction of his muscles. They seemed to ripple and string tense."; "You, Boxer, the very day that those great muscles of yours lose their power, Jones will sell you to the knacker […]"countable

3. (usually in the plural) A well-developed physique, in which the muscles are enlarged from exercise.Examples: "2008, Lou Schuler, "Foreward", in Nate Green, Built for Show, page xii The fact that I was middle-aged, bald, married, and raising girls instead of chasing them didn't really bother me. Muscles are cool at any age."countableplural-normallyuncountable

4. (uncountable, figurative) Strength, force.Examples: "The widely-backed campaign to recall Evan Mecham as governor of Arizona gained even more muscle when the state House of Representatives voted to impeach the ultraconservative on February 5."; "The lesson to be drawn from the events of 1914, to Roosevelt's mind, was that civilization needed muscle to defend it, not just solemn words."; "It was going to take muscle to pluck Miss Agnes out of the canal."figurativelyuncountable

5. (uncountable, figurative) Hired strongmen or bodyguards.Examples: "It was easy enough to dodge him, let him crash into the floorboards. Peltroc knew that his priority was the leader, not the hired muscle."figurativelyuncountable