pretext       
noun [ C ] uk/ˈpriː.tekst/ us/ˈpriː.tekst/
 借口,托词
a pretended reason for doing something that is used to hide the real reason
  The border dispute was used as a pretext for military intervention. 边界纠纷被用作军事入侵的借口。 
 I called her on the pretext of needing more information. 我借口需要更多的信息给她打了电话。 
 He came round to see her on some flimsy (= obviously false) pretext. 他找了个明显站不住脚的借口来看她。 
 Compare: guise