A group of
organs,
vessels,
glands, other
tissues, and/or
pathways which work together to perform a body function within a
multicellular organism. Examples of organ systems include the
nervous system, the
digestive system, the
immune system, and the
lymphatic system.
From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.