One of the three domains of life (the others being bacteria and archea), also called Eukarya. These are organisms whose cells are enclosed in membranes and possess a nucleus. They comprise almost all multicellular and many unicellular organisms, and are traditionally divided into groups (sometimes called kingdoms) including Animals; plants; fungi; and various algae and other taxa that were previously part of the old kingdom Protista. [ http://tolweb.org/Eukaryotes ]