[1] : The Collaborative International Dictionary of English v.0.48

dicentra \dicen"tra\ d-ise^n"tr.a, prop. n. nl., fr.
   gr. di- = di`s- twice + ke`ntron spur. bot.
   a genus of herbaceous plants, with racemes of two-spurred or
   heart-shaped flowers, including the dutchman's breeches,
   and the more showy bleeding heart dicentra spectabilis.
   corruptly written dielytra.
   1913 webster
see also:
dutchman's breeches bleeding heart dicentra spectabilis dielytra 

[2] : WordNet (r) 2.0

bleeding heart
     n 1: garden plant having deep-pink drooping heart-shaped flowers
          syn: lyreflower, lyre-flower, dicentra spectabilis
     2: someone who is excessively sympathetic toward those who
        claim to be exploited or underprivileged
see also:
lyreflower lyre-flower dicentra spectabilis 

[3] : Moby Thesaurus II by Grady Ward, 1.0

64 moby thesaurus words for "bleeding heart":
   aching heart, agony, agony of mind, anguish, bale, bathos,
   bitterness, bowels of compassion, broken heart, brokenheartedness,
   cloyingness, compassionateness, crushing, depression,
   depth of misery, desolation, despair, extremity, gentleness, goo,
   grief, heartache, heartbreak, heartbrokenness, hearts-and-flowers,
   heartsickness, heartsoreness, heavy heart, infelicity, lenity,
   maudlinness, mawkishness, melancholia, melancholy, mercifulness,
   misery, mush, mushiness, namby-pamby, namby-pambyism,
   namby-pambyness, nostalgia, nostomania, oversentimentalism,
   oversentimentality, prostration, romanticism, ruthfulness, sadness,
   sentiment, sentimentalism, sentimentality, slop, sloppiness, slush,
   soap opera, sob story, softheartedness, suicidal despair,
   sweetness and light, tearjerker, tenderness, woe, wretchedness

Bleeding Heart >> B Words
Bleeding Heart, definition of term: Bleeding Heart
bleeding+heart_pag1.html

Heart >> H Words
Heart, definition of term: Heart
heart_pag1.html

Bleeding >> B Words
Bleeding, definition of term: Bleeding
bleeding_pag1.html

Heart Condition >> H Words
Heart Condition, definition of term: Heart Condition
heart+condition_pag1.html

Heart Attack >> H Words
Heart Attack, definition of term: Heart Attack
heart+attack_pag1.html

Enlarged Heart >> E Words
Enlarged Heart, definition of term: Enlarged Heart
enlarged+heart_pag1.html

By Heart >> B Words
By Heart, definition of term: By Heart
by+heart_pag1.html