Fink (noun)

1. A person who informs on others, especially to the authorities.
2. A person who is disloyal to friends or associates, especially by betraying them to the authorities.

Origin:

Fink comes from yiddish word "faynik" meaning a strikebreaker, the word was adopted and popularized by the american labor movement in the early 20th century, but it is considered offensive and derogatory today.

Examples:

1. The employee was labeled as a fink for informing on his colleagues to the boss.
2. He was called a fink for betraying the group to the police.
3. The individual was seen as a fink for not standing up for his friends.
4. The word fink is considered a derogatory term and should not be used.
5. The term is often used to describe someone who is seen as a traitor or a snitch.