| Noun | 1. | animal tissue - the tissue in the bodies of animals nervous system, systema nervosum - the sensory and control apparatus consisting of a network of nerve cells neuropil, neuropile - the complex network of unmyelinated axones, dendrites, and glial branches that form the bulk of the central nervous system's grey matter and in which nerve cell bodies are embedded gray matter, gray substance, grey matter, grey substance, substantia grisea - greyish nervous tissue containing cell bodies as well as fibers; forms the cerebral cortex consisting of unmyelinated neurons substantia alba, white matter - whitish nervous tissue of the CNS consisting of neurons and their myelin sheaths |