What term describes unicellular eukaryotic organisms that are distinct from multicellular plants and animals?

The term that describes unicellular eukaryotic organisms that are distinct from multicellular plants and animals is "Protista." The Protista kingdom includes a diverse group of organisms, many of which are unicellular, such as amoebas and paramecia. These organisms possess a true nucleus and other membrane-bound organelles, which differentiates them from prokaryotic organisms found in the Monera kingdom. While some protists, like algae, can be multicellular, the defining characteristic is their status as eukaryotes. This highlights their separation from both multicellular organisms (like plants and animals) and simpler prokaryotic organisms.