Keeping quiet, remaining silent, zipping your lips, biting your tongue, keeping mum, shushing up, shutting your mouth, holding back, hushing, and holding your peace are some common synonyms for the phrase "hold your tongue". These expressions are used when you want someone to stop talking or to not say something that could be inappropriate, rude or offensive. It is important to understand the power of words and how they can impact others. So, it's always better to think before you speak and hold your tongue if you're unsure of the words you're about to use.