The word cast a slur is often used to mean defaming someone or tarnishing their reputation with false accusations. However, there are several antonyms for this phrase that can be used in specific contexts. One such antonym is "lavish praise," which denotes offering excessive admiration devoid of constructive criticism. Another antonym is "extol," which means to heighten or celebrate someone's strengths and virtues, highlighting their positive characteristics. Some people may use "compliment" or "applaud" in the context of an antonym for casting a slur, which generally denotes expressing genuine admiration and appreciation for someone's talents, character, or achievements. Whatever antonym you choose, be sure to use it with the right intention and in the proper context.