1mus·cle 
/ˈmʌsəl/ noun
plural mus·cles /ˈmʌsəl/ noun 1 : a body tissue that can contract and produce movement [count] ▪ the muscles of the arm ▪ stomach muscles ▪ flex a muscle ▪ relax a muscle ▪ an athlete with bulging/rippling muscles ▪ He pulled/tore/strained a muscle playing tennis. ▪ She has a strained muscle in her back. ▪ Wait here and don't move a muscle. [=don't move at all] [noncount] ▪ She started lifting weights to build muscle. — often used before another noun ▪ muscle fiber(s)/tissue ▪ muscle spasms ▪ an athlete practicing to develop muscle memory [=the ability to repeat a bodily movement exactly] ▪ a muscle relaxant [=a drug that relaxes muscles] 2 [noncount] a : physical strength
▪ She doesn't have the muscle to lift something so heavy. ▪ To clean that floor you have to put some muscle into it. [=you have to make a forceful effort]
b : power and influence
▪ He lacks the political muscle [=clout] to get the policy changed.
▪ She doesn't have the muscle to lift something so heavy. ▪ To clean that floor you have to put some muscle into it. [=you have to make a forceful effort]
b : power and influence
▪ He lacks the political muscle [=clout] to get the policy changed.
flex your muscles — see 1flex
