1. Zoomastigophora refers to the phylum more commonly known as Zooflagellates under the Kingdom Protista. They are single-celled, eukaryote, and heterotrophic and may form symbiotic relationships with other organisms, an example of which is Trichomonas. They also may be parasitic, causing diseases such as the African Sleeping Sickness, caused by the zooflagellate Trypanosoma. (Wikipedia.org)
2. A class or a taxonomic group belonging to Subphylum Mastigophora that includes colourless, heterotrophic, flagellate protozoans. (biology-online.org)