n. pl. per·i·car·di·a (-dē-ə) The membranous sac filled with serous fluid that encloses the heart and the roots of the aorta and other large blood vessels. [New Latin, from Greek perikardion, from perikardios, around the heart : peri-, peri- + kardiā, heart; see kerd- in the Appendix of Indo-European roots.] per′i·cardi·al (-dē-əl), per′i·cardi·ac′ (-dē-ăk′) adj. |
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.