Catamenia is a medical term that refers to a woman's menstrual cycle. However, there are many different synonyms that can be used to describe this process. Some of the common ones include menstruation, menses, menstrual flow, period, and menstrual cycle. Other less common synonyms include menstrual bleeding, uterine bleeding, and monthly flow. Regardless of which synonym is used, all of these terms refer to the same biological process that occurs in a woman's body every month. While some of these terms may be more formal or medical in nature, they can all be used interchangeably to discuss this important topic.