A suffix is a letter or series of letters attached to the end of a word, word base, or prefix to produce a derivative word with a new meaning. There are many suffixes used by biologists in constructing scientific names and terminology.
Kingdom is the highest rank used in the biological taxonomy of all organisms. There are 6 kingdoms in taxonomy. Every living thing comes under one of these 6 kingdoms. The six kingdoms are Eubacteria, Archae, Protista, Fungi, Plantae, and Animalia. Until the 20th century, most biologists considered all living things to be classifiable as either a plant or an animal. But in the 1950s and 1960s, most biologists came to the realization that this system failed to accommodate the fungi, protists, and bacteria. By the 1970s, a system of Five Kingdoms had come to be accepted as the model by which all living things could be classified. At a more fundamental level, a distinction was made between the prokaryotic bacteria and the four eukaryotic kingdoms (plants, animals, fungi, & protists).
Plantae, Fungi, and Animalia consist of complex, multicellular eukaryotic organisms that differ from each other in details of cell structure and in how they secure and process energy. Protista is a collection of single-celled eukaryotic organisms and simple multicellular forms, some animal-like, some plantlike. Molecular evidence, particularly from ribosomal ribonucleic acid (RNA), suggests that the five-kingdom scheme is also too simple.