organism

n. living creature; mechanism, that which functions like an organism with a system of interdependent parts

In biology and ecology, an organism (in Greek organon = instrument) is a living complex adaptive system of organs that influence each other in such a way that they function in some way as a stable whole.The origin of life on Earth and the relationships between its major lineages are controversial. Two main grades may be distinguished, the prokaryotes and eukaryotes. The prokaryotes are generally considered to represent two separate domains, called the Bacteria and Archaea, which are not closer to one another than to the eukaryotes. The gap between prokaryotes and eukaryotes is widely considered a major missing link in evolutionary history. Two eukaryotic organelles, namely mitochondria and chloroplasts, are generally considered to be derived from endosymbiotic bacteria. A similar symbiogenesis hypothesis has been proposed involving the origins of the cell nucleus, it is described as viral eukaryogenesis. Fungi, animals and plants are examples of species that are eukaryote.More recently a clade, Neomura, has been proposed, by Thomas Cavalier-Smith, which groups together the Archaea and Eukarya. Cavalier-Smith also proposed that the Neomura evolved from Bacteria, more precisely from Actinobacteria.
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Organism /or·gan·ism/ an individual living thing, whether animal or plant. pleuropneumonia-like organisms any of various bacteria of the genus [more]Organism - Community and Resources

Noun
1. a living thing that has (or can develop) the ability to act or function independently
(synonym) being
(hypernym) living thing, animate thing
(hyponym) benthos
(substance-meronym) tissue
(part-meronym) cell
(class) bioluminescent
2. a system considered analogous in structure or function to a living body; "the social organism"
(hypernym) system, scheme

(n.)
Organic structure; organization.
  

(n.)
An organized being; a living body, either vegetable or animal, compozed of different organs or parts with functions which are separate, but mutually dependent, and essential to the life of the individual.