The word "quietened" can be described using a variety of synonyms. One such synonym is "hushed," which suggests a subdued or lowered volume of sound. Another possible synonym is "calmed," which implies a reduction in excitement or tension. "Quelled" or "pacified" may also be used to describe a state of calm or tranquility. The term "muted" suggests a dulled or softened sound, while "muted" or "subdued" implies a lowered level of activity or energy. "Silenced" conveys a state of complete quiet and stillness, while "tranquilized" suggests a state of peaceful relaxation. Overall, there are many synonyms for quietened, each of which carries a slightly different connotation.