with heart

Science Dictionary
heart   (härt)  Pronunciation Key 


(click for larger image in new window)

  1. The hollow, muscular organ that pumps blood through the body of a vertebrate animal by contracting and relaxing. In humans and other mammals, it has four chambers, consisting of two atria and two ventricles. The right side of the heart collects blood with low oxygen levels from the veins and pumps it to the lungs. The left side receives blood with high oxygen levels from the lungs and pumps it into the aorta, which carries it to the arteries of the body. The heart in other vertebrates functions similarly but often has fewer chambers.

  2. A similar but simpler organ in invertebrate animals.


The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
Explore Dictionary.com
Previous Definition: with grain salt
Next Definition: with her eyes open
Words Near: with heart
More from Thesaurus.com
Synonyms and Antonyms for with heart
More from Reference.com
Search for articles containing with heart
More from Dictionary.com Translator
Dictionary.com Word FAQs

Dictionary.com presents 366 FAQs, incorporating some of the frequently asked questions from the past with newer queries.

Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature