"Mistruster" is a word used to describe someone who has a general distrust of people or things. There are many synonyms for this word that one can use to convey the same meaning. One such word is "doubter," which means someone who is unsure or skeptical about something. Another synonym for mistruster is "cynic," someone who holds negative views about people and the world. "Skeptic" is another synonym, which describes someone who is hesitant to believe something without sufficient evidence. "Pessimist" is also a synonym for mistruster, someone who always expects the worst to happen. Lastly, "paranoid" is also a synonym as this describes someone who has an unreasonable suspicion of others.