This glossary provides an overview of terms used in the description of protists, eukaryotic organisms that are neither animals nor plants nor fungi, as well as their life cycles, feeding mechanisms, and relationship with the environment. The term "protist" embraces all organisms that descended from the last eukaryotic common ancestor except those three "higher" kingdoms of life; as such, protists usually follow the same basic principles of biology as them. Nevertheless, protists exhibit almost all of the spectrum of biological characteristics expressed in eukaryotes, including many unique adaptations that are covered here.