The word "ratfink" is a colloquial term used to describe someone who is disliked or considered to be a traitor. However, there are several synonyms that can be used instead of "ratfink". One such term is "snitch" which highlights someone who gives up information or betrays secrets. Another option is "turncoat" which refers to someone who changes their allegiance or beliefs for personal gain. "Traitor" is another suitable synonym to describe someone who betrays a trust, while "backstabber" can be used to describe someone who attacks from the shadows. Overall, there are several descriptive terms that can be used instead of "ratfink" based on the context and intent of the speaker.