legalization       
noun [ U ] (UK usually legalisation) uk/ˌliː.ɡəl.aɪˈzeɪ.ʃən/ us/ˌliː.ɡəl.əˈzeɪ.ʃən/
 合法化
the act of allowing something by law
  the legalization of drugs 毒品合法化 
 She supports legalization for undocumented immigrants already in the country. 她支持让已经在该国的无证移民合法化。 
 See: legalize
 - More examples
 - He founded the group to promote the legalization of marijuana.
 - Local government officials could block the legalization of slot machine gambling in their communities.