Being calm is one of the best ways to keep yourself composed and in control of situations. However, using the same phrase every time you want to convey calmness can become monotonous. So, it's good to have a list of synonyms that you can use instead. Some of the synonyms for "be calm" include "be serene," "be tranquil," "be composed," "be peaceful," "be sedate," "be unruffled," "be mollified," "be pacified," "be relaxed," "be at ease," "be in control," and "be collected." These synonyms not only convey calmness but also emphasize different aspects of a person's demeanor and behavior. Using different words to describe being calm can make your communication more interesting and engaging.