1. Absence of a true celom or body cavity lined with mesothelium; typically found in Platyhelminthes (flatworms), which have a syncytial mass of parenchymal cells instead of a true body cavity.
The definition information for acelom is provided by Stedman's. You can search our medical dictionary here.
Stedman's, part of Lippincott Williams & Wilkins, provides a comprehensive line of health-science publications for healthcare professionals and medical students.