The antonyms for the word "most trustable" would be "least trustworthy" or "not reliable". When someone is referred to as "most trustable", it suggests that they are dependable, honest, and credible. However, the opposite would be someone who is seen as untrustworthy, deceitful, or dishonest. It is important to be cautious of individuals who are the antonyms of "most trustable", as they could potentially cause harm, be unfaithful or are not worth risking important matters. It's best to take precautions when dealing with anyone who has the opposite traits of reliability and trustworthiness.