“拉黑”用英语怎么说？

blacklist既可以作为名词，表示“黑名单”，比如说：put someone on the blacklist，把某人放到黑名单里面。
还可以作为动词，表示“拉黑”。If someone is blacklisted, they are put on a blacklist. 如果一个人被拉黑，就是说他上了黑名单。
举个例子：
Blacklisting your ex-girlfriends or ex-boyfriends is definitely the optimal way to prove your love to your current girlfriend or boyfriend. 
拉黑你的前任绝对是给现任证明爱意的最佳方式。
If someone is on a blacklist, they are seen as being one of a number of people who cannot be trusted or who have done something wrong. 如果某人被列入blacklist，他们就是被视为不可信或做了错事的人。
“拉黑”也可引申为与某个人永远断绝关系，不再联络，可以翻译为“ghost someone”，表示“end a relationship with someone suddenly by stopping all communication with them”。
举个例子：
I usually ghost my ex after the breakup.
分手后我通常都会拉黑前任。