A traitor is a person who betrays someone or something, such as a friend, cause or principle.
they see me as a traitor, a sellout to the enemy
From time to time, every spy agency falls victim to a mole, a traitor , or a double agent.
Nothing untoward happened to the traitor until he upped sticks and defected to Moscow.
Her family are adamantly opposed to her relationship and friends reject her as a traitor .
he was a traitor to his own class
The traitor will receive the information in the most discreet way possible.
Even my brothers have sent me a number of cruel e-mail accusing me of betraying the family and being a traitor .
It split the union - he was accused of being a traitor and his followers scabs.
They are traitors , and we delight in calling them scabs as they drive into work.