This is the 15436th most frequent Russian word.
предателя
"Предателя" in English means "traitor."
Here, 'предателя' is used as a noun in its accusative singular form, referring to someone who betrays others.
Он назвал его предателя из-за его поступков.
He called him a traitor because of his actions.
In this sentence, 'предателя' appears in the accusative singular form, underlining the feeling towards the person described as a traitor.
Мы были разочарованы предателя, который нас обманул.
We were disappointed with the traitor who deceived us.
The use of 'предателя' here shows it in the accusative singular form as part of an impersonal construction indicating societal judgment.