equalizer  
noun [ C ] (UK usually equaliser) uk/ˈiː.kwə.laɪ.zər/ us/ˈiː.kwə.laɪ.zɚ/
  (EQUAL)      
  使(事物或人)平等的因素,平衡器
something that makes things or people equal
  They see education as a great equalizer. 他们认为教育是促成平等的重要因素。 
 - More examples
 - Immigrants to America discovered that embracing baseball was a great equalizer.
 - The standardized exam was once thought to be an equalizer of the classes.
 - Sports were his equalizer, the one part of his life where his skin color never mattered.
 
  (POINT)      
  扳平比分的得分
the point in a game or competition that gives both teams or players the same score
  He scored an equalizer during the closing minutes of the game. 在比赛的最后几分钟里他进球将比分扳平。 
 - More examples
 - Reserve Cobi Jones scored a dramatic equalizer during injury time.
 - The equalizer came when Cullen angled a header into the corner of the net in the 41st minute.
 
  (SOUND EQUIPMENT)      
 均衡器
electronic equipment that adjusts (= makes slight changes to) the frequency of recorded sound to make it sound better
  Stereos typically have adjustable equalizers that boost or cut bass or treble frequencies. 立体声音响通常带有可调均衡器,可以加强或降低低音或高音的频率。 
 - More examples
 - The iPod's built-in equalizer made subtle changes to the sound.
 - The 10-band equalizer cranks out an awesome sound quality.
 - The mixer combines sounds from multiple sources while adjusting the volume of each source as well as shaping the sounds by way of an equalizer.