mesenchyme

mes·en·chyme

noun
\ˈmez-^ən-ˌkīm, ˈmēz-, ˈmēs-, ˈmes-\

Definition of MESENCHYME

: loosely organized undifferentiated mesodermal cells that give rise to such structures as connective tissues, blood, lymphatics, bone, and cartilage—see mesectoderm