<p><strong>Noun:</strong></p><ul><li>Anatomy: A hollow, pumplike organ of blood circulation, composed mainly of rhythmically contractile smooth muscle, located in the chest between the lungs and slightly to the left and consisting of four chambers: a right atrium that receives blood returning from the body via the superior and inferior vena cavae, a right ventricle that pumps the blood through the pulmonary artery to the lungs for oxygenation, a left atrium that receives the oxygenated blood via the pulmonary veins and passes it through the mitral valve, and a left ventricle that pumps the oxygenated blood, via the aorta, throughout the body.</li><li>Zoology: The homologous structure in other vertebrates, consisting of four chambers in mammals and birds and three chambers in reptiles and amphibians; the analogous contractile structure in invertebrate animals, as the tubular heart of the spider and earthworm.</li><li>The center of the total personality, especially with reference to intuition, feeling, or emotion: "In your heart you know I'm an honest man."</li><li>The center of emotion, especially as contrasted to the head as the center of the intellect: "His head told him not to fall in love, but his heart had the final say."</li><li>Capacity for sympathy; feeling; affection: "His heart moved him to help people in need."</li><li>Spirit, courage, or enthusiasm: "His heart sank when he walked into the room and saw their gloomy faces."</li><li>The innermost or central part of anything: "Notre Dame stands in the very heart of Paris."</li><li>The vital or essential part; core: The heart of the matter.</li><li>The breast or bosom: To clasp a person to one's heart.</li><li>A person (used especially in expressions of praise or affection): Dear heart.</li><li>A conventional shape with rounded sides meeting in a point at the bottom and curving inward to a cusp at the top.</li><li>A red figure or pip of this shape on a playing card.</li><li>A card of the suit bearing such figures.</li><li>Hearts (used with a singular or plural verb): The suit so marked: "Hearts is trump." / "Hearts are trump."</li><li>(Used with a singular verb) A game in which the players try to avoid taking tricks containing this suit.</li><li>Botany: The core of a tree; the solid central part without sap or albumen.</li><li>Good condition for production, growth, etc., as of land or crops; also called core.</li><li>Ropemaking: A strand running through the center of a rope, the other strands being laid around it.</li></ul><p><strong>Verb (used with object):</strong></p><ul><li>Archaic: To fix in the heart; to encourage.</li><li>Informal: To like or enjoy very much; love: "I heart Chicago."</li></ul>