muscle  
 noun uk/ˈmʌs.əl/ us/ˈmʌs.əl/
  (BODY PART)         
 B2 [ C or U ]肌肉 
one of many tissues in the body that can tighten and relax to produce movement
  neck/back/leg/stomach muscles 颈/背/腿/胃部肌肉 
 facial muscles 脸部肌肉 
 bulging/rippling (= large and clear to see) muscles 鼓起的肌肉 
 He flexed his muscles (= tightened them to make them look large and strong) so that everyone could admire them. 他将肌肉紧绷起来,这样大家就能欣赏到他的肌肉块。 
 These exercises build muscle and increase stamina. 这些运动能强健肌肉、增加体力。 
 a muscle spasm (= a sudden uncontrollable tightening movement) 肌肉痉挛 
 pull a muscleC1 拉伤肌肉
to injure a muscle by stretching it too far so that it is very painful
  Russell pulled a back muscle early in the game. 比赛开始没多久拉塞尔就拉伤了背部肌肉。 
 - More examples
 - The contraction of this muscle raises the lower arm.
 - A work-out in the gym will exercise all the major muscle groups.
 - He pulled a muscle in his groin.
 - Barkley suffered a strained thigh muscle late in the preseason.
 - I pulled a muscle in my back lifting some drawers.
 
  (POWER)      
 [ U ]力量,实力 
the power to do difficult things or to make people behave in a certain way
  This magazine has considerable financial muscle and can afford to pay top journalists. 这家杂志财力雄厚,能雇得起顶尖的记者。 
 The company lacks the marketing muscle to compete with drug giants. 这家公司缺乏销售实力,无法与药业巨头竞争。