"Went on the air" is a term commonly used to describe the moment when a radio or television broadcast begins. However, there are several synonyms that can be used to describe this action. To start a broadcast on the radio, you could use terms like "began broadcasting," "went live," or "started transmitting." Similarly, for television, you could use terms like "began airing," "went live," or "started showing." Regardless of the specific term used, the underlying meaning is the same: a program or message is being sent out over the airwaves to a wide audience.