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A multinucleate mass of protoplasm formed by repeated nucleus divisions without cell fission.



in animals, a type of tissue structure characterized by the absence of cell boundaries and the distribution of nuclei in a dense mass of cytoplasm. Examples of coenocytes include striated muscle fibers, the embryos of certain insects in the early stages of development, and certain protozoans, including many infusorians. Some tissues, for example, the epithelial intestinal lining of many mollusks and insects, have alternating cellular and coenocytic structures at various stages of digestion. A coenocyte may be formed by cell fusion or by the multiplication of nuclei without subsequent plasmotomy or cytotomy.

In plants the polynuclear protoplast of organisms having no cell structure, for example, Caulerpa, is referred to as either a coenocyte or syncytium. In multicellular plants the term “coenocyte” refers to the protoplasmic contents (including nuclei) of fused cells, for example, jointed lactiferous vessels, as well as to the aggregate of protoplasts connected by protoplasmic threads (plasmodesmata).