The antonym for the phrase "cleaves to" would be "separates from," "abandons," or "diverges from." When someone is cleaving to something, they are holding onto it tightly or deeply connecting with it. In contrast, when they are separating from it, they are creating distance or ending the connection. Abandoning something suggests a deliberate choice to leave it behind, and diverging from something means moving in a different direction. Understanding antonyms can help to improve your mastery of language and communication skills. It allows you to express yourself more clearly, and to effectively convey your thoughts and ideas.