When it comes to synonyms for the phrase "being on the air," there are several options to choose from depending on the context. For instance, the phrase "live broadcasting" can be used to refer to the act of being on the air, either through a TV or radio show. Another synonym is "broadcasting in real-time," which is commonly used during live news coverage. Additionally, the phrase "going live" is often used in the context of social media platforms such as Facebook or Instagram when users begin a live stream. Overall, there are numerous synonyms for "being on the air" that can be used to convey the same meaning depending on the setting.