The phrase "with one assent" means that everyone has agreed to something unanimously. There are a few synonyms for this phrase, including "with one accord," "with one voice," and "in unison." These phrases suggest that people are in agreement and have come together to support a common idea or goal. Other synonyms might include "together," "united," "harmoniously," or "unanimously." These words can convey a sense of community and cooperation, and they are often used in political or social contexts where people are striving to work together towards a common objective. Whether it's a business meeting, a political rally, or a community event, finding synonyms for "with one assent" can help us communicate our shared goals and values.