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definitions

heart

[hahrt]
noun
  1. 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.
  2. Zoology.
    1. the homologous structure in other vertebrates, consisting of four chambers in mammals and birds and three chambers in reptiles and amphibians.
    2. the analogous contractile structure in invertebrate animals, as the tubular heart of the spider and earthworm.
  3. the center of the total personality, especially with reference to intuition, feeling, or emotion: In your heart you know I'm an honest man.
  4. 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.
  5. capacity for sympathy; feeling; affection: His heart moved him to help the needy.
  6. spirit, courage, or enthusiasm: His heart sank when he walked into the room and saw their gloomy faces.
  7. the innermost or central part of anything: Notre Dame stands in the very heart of Paris.
  8. the vital or essential part; core: the heart of the matter.
  9. the breast or bosom: to clasp a person to one's heart.
  10. a person (used especially in expressions of praise or affection): dear heart.
  11. a conventional shape with rounded sides meeting in a point at the bottom and curving inward to a cusp at the top.
  12. a red figure or pip of this shape on a playing card.
  13. a card of the suit bearing such figures.
  14. hearts,
    1. (used with a singular or plural verb)the suit so marked: Hearts is trump. Hearts are trump.
    2. (used with a singular verb)a game in which the players try to avoid taking tricks containing this suit.
  15. Botany. the core of a tree; the solid central part without sap or albumen.
  16. good condition for production, growth, etc., as of land or crops.
  17. Also called core. Ropemaking. a strand running through the center of a rope, the other strands being laid around it.
verb (used with object)
  1. Archaic.
    1. to fix in the heart.
    2. to encourage.
  2. Informal. to like or enjoy very much; love: I heart Chicago.
Idioms
  1. after one's own heart, in keeping with one's taste or preference: There's a man after my own heart!
  2. at heart, in reality; fundamentally; basically: At heart she is a romantic.
  3. break someone's heart, to cause someone great disappointment or sorrow, as to disappoint in love: The news that their son had been arrested broke their hearts.
  4. by heart, by memory; word-for-word: They knew the song by heart.
  5. cross one's heart, to maintain the truth of one's statement; affirm one's integrity: That's exactly what they told me, I cross my heart!
  6. do someone's heart good, to give happiness or pleasure to; delight: It does my heart good to see you again.
  7. eat one's heart out, to have jealousy, longing, or sorrow dominate one's emotions (often used in the imperative and with jocular reference to a famous potential rival): My baby is a genius—Einstein, eat your heart out! He’s eating his heart out over his defeat.
  8. from the bottom of one's heart, with complete sincerity.Also from one's heart, from the heart.
  9. have a heart, to be compassionate or merciful: Please have a heart and give her another chance.
  10. have at heart, to have as an object, aim, or desire: to have another's best interests at heart.
  11. have one's heart in one's mouth, to be very anxious or fearful: He wanted to do the courageous thing, but his heart was in his mouth.
  12. have one's heart in the right place, to be fundamentally kind, generous, or well-intentioned: The old gentleman may have a stern manner, but his heart is in the right place.
  13. heart and soul, enthusiastically; fervently; completely: They entered heart and soul into the spirit of the holiday.
  14. in one's heart of hearts, in one's private thoughts or feelings; deep within one: He knew, in his heart of hearts, that the news would be bad.
  15. lose one's heart to, to fall in love with: He lost his heart to the prima ballerina.
  16. near one's heart, of great interest or concern to one: It is a cause that is very near his heart.Also close to one's heart.
  17. not have the heart, to lack the necessary courage or callousness to do something: No one had the heart to tell him he was through as an actor.
  18. pour out one's heart, to reveal one's thoughts or private feelings:She poured out her heart to me.Also open one's heart.
  19. set one's heart against, to be unalterably opposed to: She had set her heart against selling the statue.Also have one's heart set against.
  20. set one's heart at rest, to dismiss one's anxieties: She couldn't set her heart at rest until she knew he had returned safely.
  21. set one's heart on, to wish for intensely; determine on: She has set her heart on going to Europe after graduation.Also have one's heart set on.
  22. take heart, to regain one's courage; become heartened: Her son's death was a great blow, but she eventually took heart, convinced that God had willed it.
  23. take/lay to heart,
    1. to think seriously about; concern oneself with: He took to heart his father's advice.
    2. to be deeply affected by; grieve over: She was prone to take criticism too much to heart.
  24. to one's heart's content, until one is satisfied; as much or as long as one wishes: The children played in the snow to their heart's content.
  25. wear one's heart on one's sleeve,
    1. to make one's intimate feelings or personal affairs known to all: She was not the kind who would wear her heart on her sleeve.
    2. to be liable to fall in love; fall in love easily: How lovely to be young and wear our hearts on our sleeves!
  26. with all one's heart,
    1. with earnestness or zeal.
    2. with willingness; cordially: She welcomed the visitors with all her heart.

Origin of heart

before 900; Middle English herte, Old English heorte; cognate with Dutch hart, German Herz, Old Norse hjarta, Gothic hairtō; akin to Latin cor (see cordial, courage), Greek kardía (see cardio-); def 19, from the use of the stylized heart symbol to represent love
Can be confusedhart heart
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for wear one's heart on one's sleeve

heart

noun
  1. the hollow muscular organ in vertebrates whose contractions propel the blood through the circulatory system. In mammals it consists of a right and left atrium and a right and left ventricleRelated adjective: cardiac
  2. the corresponding organ or part in invertebrates
  3. this organ considered as the seat of life and emotions, esp love
  4. emotional mood or dispositiona happy heart; a change of heart
  5. tenderness or pityyou have no heart
  6. courage or spirit; bravery
  7. the inmost or most central part of a thingthe heart of the city
  8. the most important or vital partthe heart of the matter
  9. (of vegetables such as cabbage) the inner compact part
  10. the core of a tree
  11. the part nearest the heart of a person; breastshe held him to her heart
  12. a dearly loved person: usually used as a term of addressdearest heart
  13. a conventionalized representation of the heart, having two rounded lobes at the top meeting in a point at the bottom
    1. a red heart-shaped symbol on a playing card
    2. a card with one or more of these symbols or (when pl.) the suit of cards so marked
  15. a fertile condition in land, conducive to vigorous growth in crops or herbage (esp in the phrase in good heart)
  16. after one's own heart appealing to one's own disposition, taste, or tendencies
  17. at heart in reality or fundamentally
  18. break one's heart or break someone's heart to grieve or cause to grieve very deeply, esp through love
  19. by heart by committing to memory
  20. cross my heart! or cross my heart and hope to die! I promise!
  21. eat one's heart out to brood or pine with grief or longing
  22. from one's heart or from the bottom of one's heart very sincerely or deeply
  23. have a heart! be kind or merciful
  24. have one's heart in it (usually used with a negative) to have enthusiasm for something
  25. have one's heart in one's boots to be depressed or down-hearted
  26. have one's heart in one's mouth or have one's heart in one's throat to be full of apprehension, excitement, or fear
  27. have one's heart in the right place
    1. to be kind, thoughtful, or generous
    2. to mean well
  28. have the heart (usually used with a negative) to have the necessary will, callousness, etc (to do something)I didn't have the heart to tell him
  29. heart and soul absolutely; completely
  30. heart of hearts the depths of one's conscience or emotions
  31. heart of oak a brave person
  32. in one's heart secretly; fundamentally
  33. lose heart to become despondent or disillusioned (over something)
  34. lose one's heart to to fall in love with
  35. near to one's heart or close to one's heart cherished or important
  36. set one's heart on to have as one's ambition to obtain; covet
  37. take heart to become encouraged
  38. take to heart to take seriously or be upset about
  39. to one's heart's content as much as one wishes
  40. wear one's heart on one's sleeve to show one's feelings openly
  41. with all one's heart or with one's whole heart very willingly
verb
  1. (intr) (of vegetables) to form a heart
  2. an archaic word for hearten
See also hearts

Word Origin for heart

Old English heorte; related to Old Norse hjarta, Gothic hairtō, Old High German herza, Latin cor, Greek kardia, Old Irish cride
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for wear one's heart on one's sleeve

heart

n.

Old English heorte "heart; breast, soul, spirit, will, desire; courage; mind, intellect," from Proto-Germanic *khertan- (cf. Old Saxon herta, Old Frisian herte, Old Norse hjarta, Dutch hart, Old High German herza, German Herz, Gothic hairto), from PIE *kerd- "heart" (cf. Greek kardia, Latin cor, Old Irish cride, Welsh craidd, Hittite kir, Lithuanian širdis, Russian serdce "heart," Breton kreiz "middle," Old Church Slavonic sreda "middle").

Spelling with -ea- is c.1500, reflecting what then was a long vowel, and remained when pronunciation shifted. Most of the figurative senses were present in Old English, including "intellect, memory," now only in by heart. Heart attack attested from 1875; heart disease is from 1864. The card game hearts is so called from 1886.

Online Etymology Dictionary, © 2010 Douglas Harper
wear one's heart on one's sleeve in Medicine

heart

[härt]
n.
  1. 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. A similarly functioning structure in invertebrates.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
wear one's heart on one's sleeve in Science

heart

[härt]
  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 © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
wear one's heart on one's sleeve in Culture

wear one's heart on one's sleeve

To express affection or sentiment too openly or ostentatiously: “You have to play it cool with a girl like Heidi; you mustn't wear your heart on your sleeve.”

heart

The hollow muscular organ that is the center of the circulatory system. The heart pumps blood throughout the intricate system of blood vessels in the body.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Idioms and Phrases with wear one's heart on one's sleeve

wear one's heart on one's sleeve

Also, pin one's heart on one's sleeve. Openly show one's feelings, especially amorous ones. For example, You can't help but see how he feels about her; he wears his heart on his sleeve. This expression alludes to the former custom of tying a woman's favor to her lover's sleeve, thereby announcing their attachment. Shakespeare had it in Othello (1:1): “But I will wear my heart upon my sleeve for daws to peck at.”

heart

In addition to the idioms beginning with heart

  • heart and soul
  • heart goes out to, one's
  • heart in it, have one's
  • heart in one's mouth, have one's
  • heart in the right place, have one's
  • heart is set on
  • heart misses a beat, one's
  • heart not in it
  • heart of gold
  • heart of stone
  • heart of the matter
  • heart on one's sleeve
  • heart sinks, one's
  • heart stands still
  • heart to heart

also see:

  • absence makes the heart grow fonder
  • after one's own heart
  • at heart
  • break someone's heart
  • by heart
  • change of heart
  • cold hands, warm heart
  • cross my heart
  • cry one's eyes (heart) out
  • cut to the quick (heart)
  • do one (one's heart) good
  • eat one's heart out
  • find it in one's heart
  • from the bottom of one's heart
  • get to the heart of
  • give someone heart failure
  • half a heart
  • harden one's heart
  • have a heart
  • have no heart for
  • heavy heart
  • in one's heart of hearts
  • lose heart
  • lose one's heart to
  • near to one's heart
  • not have the heart to
  • open one's heart
  • pour out one's heart
  • set one's heart on
  • sick at heart
  • steal someone's heart
  • steel one's heart against
  • take heart
  • take to heart
  • to one's heart's content
  • warm heart
  • warm the cockles of one's heart
  • wear one's heart on one's sleeve
  • with all one's heart
  • young at heart
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.