noun, plural: animals
(1) being eukaryotic (i.e. the cell contains a membrane-bound nucleus) and usually multicellular (unlike bacteria and most protists, an animal is composed of several cells performing specific functions)
Of or relating to animals, e.g. animal functions.
The following are the grand divisions, or subkingdoms, and the principal classes under them, generally recognized at the present time: Vertebrata, including Mammalia or mammals, Aves or birds, Reptilia, Amphibia, Pisces or fishes, Marsipobranchiata (Craniota); and Leptocardia (Acrania). Tunicata, including the Thaliacea, and Ascidioidea or ascidians. Articulata or Annulosa, including Insecta, Myriapoda, Malacapoda, Arachnida, Pycnogonida, Merostomata, Crustacea (Arthropoda); and Annelida, Gehyrea (Anarthropoda). Helminthes or vermes, including Rotifera, Chaetognatha, Nematoidea, Acanthocephala, Nemertina, Turbellaria, Trematoda, Cestoidea, Mesozea. Molluscoidea, including Brachiopoda and Bryozoa. Mollusca, including Cephalopoda, Gastropoda, Pteropoda, Scaphopoda, Lamellibranchiata or Acephala. Echinodermata, including Holothurioidea, Echinoidea, Asterioidea, Ophiuroidea, and Crinoidea. Coelenterata, including Anthozoa or polyps, Ctenophora, and Hydrozoa or Acalephs. Spongiozoa or Porifera, including the sponges. Protozoa, including Infusoria and Rhizopoda. For definitions, see these names in the vocabulary.
Related forms: Animalia (noun), animalian (adjective).