"Art all ears" is an idiomatic expression used to convey an avid listener or someone who is eagerly waiting to hear something interesting. However, its antonym would be "deaf to you," which implies a complete lack of interest or attention towards what is being spoken. Other antonyms for "art all ears" include "inattentive," "disinterested," "unresponsive," or "indifferent." These words suggest a notable lack of enthusiasm or involvement in the conversation. Therefore, understanding antonyms of phrases or words can help improve one's language skills and develop a broader vocabulary to express different emotions and attitudes.