pericardium

noun

peri·​car·​di·​um ˌper-ə-ˈkär-dē-əm 

plural pericardia ˌper-ə-ˈkär-dē-ə 

1

: the conical sac of serous membrane that encloses the heart and the roots of the great blood vessels of vertebrates

2

: a cavity or space that contains the heart of an invertebrate and in arthropods is a part of the hemocoel

Examples of pericardium in a Sentence

Recent Examples on the Web

Anthony Figueiredo, a British priest with the Diocese of Assisi, handles a sliver of the boy's pericardium — the sac that surrounds the heart — that is touring the world as a religious relic. —Ruth Sherlock, NPR, 7 Sep. 2025

This is different than fluid being in the lung tissue itself or in the pericardium. —Dr. John De Jong, Boston Herald, 14 July 2024

In May, Pearce announced that she had been diagnosed with a heart condition called pericarditis, a swelling and irritation of the pericardium, the thin, saclike tissue that surrounds the heart, according to the Mayo Clinic. —Melissa Locker, Southern Living, 25 June 2024

The heart gets not one but two bags: a tough outer fibrous pericardium and a serous pericardium, protecting the heart and fixing it firmly in place in our constantly moving thorax. —Bethany Brookshire, Scientific American, 27 Dec. 2023

Word History

Etymology

Middle English, from Medieval Latin, from Greek perikardion, neuter of perikardios around the heart, from peri- + kardia heart — more at heart

First Known Use

15th century, in the meaning defined at sense 1

Rhymes for pericardium

• endocardium
• myocardium

Kids Definition

pericardium

noun

peri·​car·​di·​um ˌper-ə-ˈkärd-ē-əm 

plural pericardia -ē-ə 

: the cone-shaped structure of membrane that encloses the vertebrate heart and the nearby parts of the large arteries and veins leading to or away from it

pericardial

-ē-əl

adjective

Medical Definition

pericardium

noun

peri·​car·​di·​um ˌper-ə-ˈkärd-ē-əm 

plural pericardia -ē-ə 

: the conical sac of serous membrane that encloses the heart and the roots of the great blood vessels of vertebrates and consists of an outer fibrous coat that loosely invests the heart and is prolonged on the outer surface of the great vessels except the inferior vena cava and a double inner serous coat of which one layer is closely adherent to the heart while the other lines the inner surface of the outer coat with the intervening space being filled with pericardial fluid