declassify verb [ T ] uk/ˌdiːˈklæs.ɪ.faɪ/ us/ˌdiːˈklæs.ə.faɪ/
解密，公开（尤指政治或军事信息）to say officially that political or military information is no longer secret
Many government documents are declassified after 50 years. 50年后许多政府文件都解密了。
Related word: declassification