Zoomastigote is a word that describes a group of single-celled organisms that have a whip-like tail called a flagellum. However, there are few synonyms that can be used to describe these organisms. One possible synonym is flagellate, which refers to any organism that has one or more flagella. This term can be used to describe bacteria, protozoans, and algae that have a flagellum. Another synonym for zoomastigote is Mastigophora, which is an extinct phylum of unicellular organisms that were characterized by the presence of flagella. Lastly, the term zooflagellate could also be used as a synonym, which refers to flagellates that are found in animals.