Being disloyal to someone or something means betraying their trust or breaking a promise. Antonyms for being loyal to can include unfaithful, deceitful, treacherous, or faithless. Being unfaithful refers to breaking a commitment or vow, while deceitful involves dishonesty or trickery. Someone who is treacherous may act in a way that is harmful or disloyal to others, and a faithless person lacks loyalty, trust, and confidence. It is important to recognize and understand the antonyms for being loyal to in order to avoid acting in a manner that could damage relationships or cause harm to others.