Definition of: mesenchyme

(mes′eng·kim) noun Biol.
The portion of the mesoderm that produces the connective tissues of the body, the blood vessels, lymphatic system, and heart. It is cellular in structure, and in some of the lower forms of life is the same as mesoblast. Also mes·en·chy·ma (mes·eng′kə·mə). [<NL mesenchyma <MES- + Gk. en- in + chein pour]
—mes·en′·chy·mal, mes′en·chym′a·tous (-kim′ə·təs) adjective