在上面的报道中，tip-off就是指“揭发、举报”，例如：Acting on a tip-off, the police arrested the drug smugglers.（警方根据密报逮捕了毒品走私者）。Tip在这里做名词，表示“秘密消息”。 此外，其动词形式tip off表示“通风、告密”等意思，比如：Did Nancy want him to tip off ...

请看相关报道： All provincial courts on China's mainland have launched websites to collect tips against corrupted judges, following the launch of a tip-off website by the Supreme People's Court (SPC).