Chewing the fat is a phrase that means to have a casual conversation or engage in idle chat. Some antonyms for this phrase could include focused discussion, purposeful conversation, or serious debate. Instead of wasting time with trivial topics, individuals engaging in these antonyms would be striving for productivity and meaningful communication. Additionally, one could opt for brief interactions, rather than lengthy ones, to avoid simply passing the time. In this way, antonyms for chewing the fat would highlight the importance of valuing one's time and focusing on valuable, productive communication.