mispronunciation       
noun [ C or U ] uk/ˌmɪs.prəˌnʌn.siˈeɪ.ʃən/ us/ˌmɪs.prəˌnʌn.siˈeɪ.ʃən/
 错误的发音
the act of pronouncing a word or sound wrongly, or an example of this
  Mispronunciation can be a serious obstacle to making yourself understood in a foreign language. 错误的发音可能会严重阻碍你用外语表达自己的意思。 
 I made a slight mispronunciation and the girl behind the counter didn't understand me. 我的发音有点小错误,柜台后面的女孩没听懂我的话。 
 See: mispronounce
 - More examples
 - Thank you very much for overlooking my mispronunciations.
 - He was known for his occasional mispronunciation of medical terms.
 - You wouldn't get upset over the mispronunciation of a word, would you?