If you call someone a traitor, you mean that they have betrayed beliefs that they used to hold, or that their friends hold, by their words or actions.
例句
Some say he's a traitor to the working class.一些人说他是工人阶级的叛徒。
N-COUNT
(尤指战时的)卖国贼,叛徒
If someone is a traitor, they betray their country or a group of which they are a member by helping its enemies, especially during time of war.
例句
...rumours that there were traitors among us who were sending messages to the enemy.关于我们中间有叛徒向敌人通风报信的传言
英汉词典释义
n.
卖国贼;叛徒
He denounced her as traitor.他指责她是叛徒。He was publicly denounced as a traitor.他被公开谴责为叛徒。He was sold out by a traitor and arrested.他被叛徒出卖而被捕了。All traitorous persons and cliques came to no good end.所有的叛徒及叛徒集团都没好下场。He was depicted as a traitor.他被描绘成卖国贼。
背叛者;背信弃义的人
He turned traitor to our cause.他背叛了我们的事业
英英词典释义
Noun
1. someone who betrays his country by committing treason