Betted on can have several antonyms depending on the context of the phrase. If it refers to a certain outcome, the antonym could be "avoided" or "opposed." However, if "betted on" pertains to a person, the antonym could be "doubted" or "ignored." Additionally, "betted against" or "betted off" can also be considered antonyms of "betted on" depending on the situation. In simpler terms, an antonym for "betted on" can be any word that implies the opposite of placing confidence or hope in a certain thing or person.