"Order Sirenia" refers to a group of marine mammals that includes manatees and dugongs. There are several synonyms for this term, including the order "Sirenidae", "Sirenians", and "Sea cows". The term "Sirenidae" is used to refer to a specific family within the Order Sirenia, while "Sirenians" is a broader term that encompasses all members of the Order. "Sea cows" is a colloquial term that is sometimes used to describe members of the Order Sirenia due to their large size and herbivorous diet. Regardless of which term is used, it is important to recognize and protect these fascinating marine creatures and their habitats.