Call waiting is a term used for a service that allows someone to receive another call while they are already on a phone call. There are several synonyms for call waiting, such as "ringing-in," "waiting call," "beeping," "call hold," and "call interjection." These terms are used to describe the same function as call waiting, which is to notify the recipient of another incoming call. Whether it's using call waiting or one of its many synonyms, the idea remains the same - to juggle multiple incoming calls with ease and efficiency. So, it's essential to understand the synonyms and how they are used in different situations.