hemicardia

[hĕm′ĭ-kärdē-ə]
n.
  1. Either lateral half of the heart, including the atrium and ventricle.
  2. A congenital malformation of the heart in which only two of the usual four chambers are formed.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.