There are several antonyms for the word "blethers", which means to talk excessively or foolishly. One antonym for this word could be "listen", which is the act of paying attention to someone else while they speak. Another antonym is "be quiet" or "stop talking", which means to cease talking altogether. Additionally, "concise" and "pithy" can be antonyms for "blethers", as both words refer to concise and meaningful communication. Other antonyms that can be considered are "focused" or "organized", as these words refer to having a clear and direct communication style. Overall, there are many ways to express the opposite of "blethers".