heart

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Anatomy The chambered muscular organ in vertebrates that pumps blood received from the veins into the arteries, thereby maintaining the flow of blood through the entire circulatory system.
2. n. Anatomy A similarly functioning structure in invertebrates.
3. n. The area that is the approximate location of the heart in the body; the breast.
4. n. The vital center and source of one's being, emotions, and sensibilities.
5. n. The repository of one's deepest and sincerest feelings and beliefs: an appeal from the heart; a subject dear to her heart.
6. n. The seat of the intellect or imagination: the worst atrocities the human heart could devise.
7. n. Emotional constitution, basic disposition, or character: a man after my own heart.
8. n. One's prevailing mood or current inclination: We were light of heart.
9. n. Capacity for sympathy or generosity; compassion: a leader who seems to have no heart.
10. n. Love; affection: The child won my heart.
11. n. Courage; resolution; fortitude: The soldiers lost heart and retreated.
12. n. The firmness of will or the callousness required to carry out an unpleasant task or responsibility: hadn't the heart to send them away without food.
13. n. A person esteemed or admired as lovable, loyal, or courageous: a dear heart.
14. n. The central or innermost physical part of a place or region: the heart of the financial district. See Synonyms at center.
15. n. The core of a plant, fruit, or vegetable: hearts of palm.
16. n. The most important or essential part: get to the heart of the matter.
17. n. A conventional two-lobed representation of the heart, usually colored red or pink.
18. n. Games A red, heart-shaped figure on certain playing cards.
19. n. Games A playing card with this figure.
20. n. Games The suit of cards represented by this figure.
21. n. Games A card game in which the object is either to avoid hearts when taking tricks or to take all the hearts.
22. v. Archaic To encourage; hearten.
23. idiom. at heart In one's deepest feelings; fundamentally.
24. idiom. by heart Learned by rote; memorized word for word.
25. idiom. do (one's) heart good To lift one's spirits; make one happy.
26. idiom. bottom With the deepest appreciation; most sincerely.
27. idiom. have (one's) heart in (one's) mouth To be extremely frightened or anxious.
28. idiom. have (one's) heart in the right place To be well-intentioned.
29. idiom. heart and soul Completely; entirely.
30. idiom. in (one's) heart of hearts In the seat of one's truest feelings.
31. idiom. lose (one's) heart to To fall in love with.
32. idiom. near Loved by or important to one.
33. idiom. steal (someone's) heart To win one's affection or love.
34. idiom. take to heart To take seriously and be affected or troubled by: Don't take my criticism to heart.
35. idiom. to (one's) heart's content To one's entire satisfaction, without limitation.
36. idiom. wear (one's) heart on (one's) sleeve To show one's feelings clearly and openly by one's behavior.
37. idiom. with all (one's) heart With great willingness or pleasure.
38. idiom. with all (one's) heart With the deepest feeling or devotion.
39. idiom. with half a heart In a halfhearted manner.

Century Dictionary and Cyclopedia

1. n. The principal organ of the circulation of the blood in man and other animals; the physiological center of the blood-vascular system. It is a hollow muscular or otherwise contractile organ which receives blood in its interior, and by contractions or pulsations drives it out again, and thus keeps up the circulation of this fluid. In its simplest form, as in the early embryo of a vertebrate and in many invertebrate animals, it is simply an expanded part or expansion in the course of a blood-vessel, capable of beating, pulsating, or alternately dilating and contracting, and so acting upon the contained fluid mechanically. (See cuts under Astacidæ and Balanoglossus.) In the process of development one or both orifices of this bulb are furnished with a valve permitting the flow of blood in one direction and preventing it in the other; and the bulb is partly divided by a constriction across it, one of the resulting parts being specially devoted to the reception of blood, as from a vein, and its transmission only into the other part, which then by contraction urges it onward, as into an artery. This is the structure of the two-chambered or bilocular heart of the lower vertebrates, in which the receiving-chamber is the auricle, the distributing-chamber is the ventricle, and the communication between them is the auriculoventricular opening. In a more complex form the bilocular heart is partly divided into right and left halves by a constriction or partition which separates the single auricle into two, the result being the three-chambered or trilocular heart, in which one auricle, the right, receives venous blood from the body at large, the left auricle receives aërated or arterial blood from gills or lungs, and each auricle pours its blood through its own auriculoventricular orifice into a common and single ventricle, which then sends a current of mixed venous and arterial blood to all parts of the body. Such is the type of the reptilian heart; though the right and left auricles are in fact incompletely separated from each other, retaining an interauricular opening, which in the embryos of birds and mammals is known as the foramen ovale. Finally, the entire separation of the auricles, and complete division of a common ventricular cavity into a right and a left ventricle by an interventricular septum or partition, result in the perfectly four-chambered or quadrilocular heart of all adult vertebrates above reptiles. Here the right and left sides of the heart, each consisting of an auricle and a ventricle, are entirely separate, so that no mixture of venous and arterial currents is possible. (See circulation of the blood, under circulation.) The ventricles are larger and more muscular than the auricles, since the former have to drive the blood through the body, while the auricles have only to inject it into the ventricles. All the orifices of the heart are more or less completely guarded by sets of valves. The right auriculoventricular valves are called tricuspid; the left, mitral: in both cases from their form in the human heart, in which three membranous valves on the right side and two on the left are operated by delicate fibrous cords (the chordæ tendineæ) and certain muscular processes from the ventricular walls (the columnæ carneæ). The orifices of the aorta and of the pulmonary artery are alike guarded by three crescentic valves, called, from their shape, the semilunar valves. The orifices by which veins enter either auricle either are or are not provided with valves, in different cases, or in different animals. The contraction of the muscular walls of the heart as a whole, or of any one of its chambers, is the systole; the corresponding and alternating dilatation of its cavities, or any one of them, is the diastole; the two movements together complete a cardiac cycle. In vertebrates the heart is situated in the thorax, between the lungs, and enveloped in a serous membrane, the pericardium, which is generally a closed sac with one layer, the visceral or cardiac pericardium, or epicardium, investing the whole surface of the organ and the roots of the great vessels which spring from it, and the other, the parietal layer, reflected over the surface of adjacent structures. The primitive position of the heart is always median; but in the course of its development from the embryo it generally becomes tilted over to one side, the left, as is usual in the higher vertebrates, where the point or apex of the organ lies considerably to the left, and the whole organ becomes unsymmetrical both in its own shape and in its relative position. In general the form of the heart is conoidal, with the base (the auricles) upward or forward, and the apex (the ventricles) downward or backward and sinistral. In man the heart is about 5 inches long, 3½ inches in greatest width, and 2 inches in greatest depth; it weighs 10 or 12 ounces in the male, and 8 or 10 in the female. It lies obliquely in the chest, with its broad fixed base uppermost, a little backward and to the right; its free apex downward, forward, and to the left, so that its beating may be seen or felt at a point an inch or less to the inner side of, and about an inch and a half below, the left nipple, between the fifth and sixth ribs. All the cavities of the heart are lined with a thin smooth membrane, the endocardium, which also invests the valves and is directly continuous with the lining of all the vessels which enter or leave the heart. Its substance, the myocardium, is almost entirely muscular; the muscle is a peculiar striated one, of a deep-red color; its fibers are intricately disposed in two sets, auricular and ventricular, separated by fibrous rings which surround the auriculoventricular orifices. It is supplied with blood for its own nourishment by the right and left coronary arteries, the first branches of the aorta; they are accompanied by cardiac veins. Its nerves are derived from the cardiac plexuses, formed by the pneumogastric and sympathetic nerves. Its action is involuntary. In all other mammals, and in birds, the heart is substantially the same as in man, with differences in relative size, in shape, and in the detail of its openings and valves; but in the acranial vertebrates, the lancelets, it is rudimentary. See also cuts under circulation, embryo, lung, and thorax.
2. n. The human heart or breast considered as the seat of all or of some of the mental faculties; hence, in common figurative use, these faculties themselves. The emotions and affections, especially moral capacity or disposition, as for love or hatred, benevolence or malevolence, pity or scorn, courage or fear, faith or distrust, etc.
3. n. The intellectual faculties; especially, inmost or most private thought; innermost opinions or convictions; genuine or intense desire or sentiment: as, she despised him in her heart; the heart of a man is unsearchable; the devices of the heart; to set one's heart upon something.
4. n. Good feeling; love; kindness; sensibility: as, she is all heart; he is all head and no heart; to gain one's heart; to give the heart to God.
5. n. Courage; spirit; determination; firmness of will; capacity for perseverance or endurance: as, to take heart; his heart failed him.
6. n. The breast, as covering the heart, considered as the seat of affection.
7. n. The inner part of anything; the middle or center: as, the heart of a country or a town.
8. n. The chief, vital, or most essential part; the vigorous or efficacious part; the core.
9. n. A person, especially a brave or affectionate person: used as a term of encouragement, praise, or endearment.
10. n. Strength; power of producing; vigor; fertility: as, to keep the land in heart.
11. n. Something that has the shape or form of heart; especially, a roundish or an oval figure or object having an obtuse point at one end and a corresponding indentation or depression at the other, regarded as representing the figure of a heart; especially, such a figure on a playing-card.
12. n. One of a suit of playing-cards marked with such a figure.
13. n. plural A game of cards played with the full pack by four persons. The rules are the same as in whist, except that there are no partners and no trump, and that the tricks count nothing, but at the end of the hand the player who has taken the fewest hearts receives a counter from each of the others for each heart that other has taken. The game is also played with variations from these rules.
14. n. Nautical, a block of hard wood in the shape of a heart for the lanyards of stays to reeve through.
15. n. In botany, the core of a tree; the solid central part without sap or albumen. See heart-wood.
16. To give heart to; encourage; hearten.
17. In masonry, to build, as the interior of a rubble wall, solidly with stone and mortar.
18. To form a close, compact head, as a plant; especially, to have the central part of the head close and compact: as, some varieties of cabbage heart well.
19. n. An excessive deposit of fat around the heart.

Wiktionary

1. n. anatomy A muscular organ that pumps blood through the body, traditionally thought to be the seat of emotion.
2. n. uncountable Emotions, kindness, moral effort, or spirit in general.
3. n. A conventional shape or symbol used to represent the heart, love, or emotion: ♥ or sometimes <3.
4. n. A playing card of the suit hearts featuring one or more heart-shaped symbols.
5. n. The centre, essence, or core.
6. v. transitive To be fond of. Often bracketed or abbreviated with a heart symbol.
7. v. transitive, obsolete To encourage.
8. v. transitive, masonry To fill an interior with rubble, as a wall or a breakwater.
9. v. intransitive, agriculture, botany To form a dense cluster of leaves, a heart, especially of lettuce or cabbage.

GNU Webster's 1913

1. n. (Anat.) A hollow, muscular organ, which, by contracting rhythmically, keeps up the circulation of the blood.
2. n. The seat of the affections or sensibilities, collectively or separately, as love, hate, joy, grief, courage, and the like; rarely, the seat of the understanding or will; -- usually in a good sense, when no epithet is expressed; the better or lovelier part of our nature; the spring of all our actions and purposes; the seat of moral life and character; the moral affections and character itself; the individual disposition and character.
3. n. The nearest the middle or center; the part most hidden and within; the inmost or most essential part of any body or system; the source of life and motion in any organization; the chief or vital portion; the center of activity, or of energetic or efficient action
4. n. Courage; courageous purpose; spirit.
5. n. Vigorous and efficient activity; power of fertile production; condition of the soil, whether good or bad.
6. n. That which resembles a heart in shape; especially, a roundish or oval figure or object having an obtuse point at one end, and at the other a corresponding indentation, -- used as a symbol or representative of the heart.
7. n. One of the suits of playing cards, distinguished by the figure or figures of a heart.
8. n. Vital part; secret meaning; real intention.
9. n. A term of affectionate or kindly and familiar address.
10. v. obsolete To give heart to; to hearten; to encourage; to inspirit.
11. v. To form a compact center or heart.

WordNet 3.0

1. n. a plane figure with rounded sides curving inward at the top and intersecting at the bottom; conventionally used on playing cards and valentines
2. n. an area that is approximately central within some larger region
3. n. a firm rather dry variety meat (usually beef or veal)
4. n. the choicest or most essential or most vital part of some idea or experience
5. n. a playing card in the major suit that has one or more red hearts on it
6. n. the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions move the blood through the body
7. n. a positive feeling of liking
8. n. the locus of feelings and intuitions
9. n. the courage to carry on
10. n. an inclination or tendency of a certain kind