1. a person who is excessively sympathetic to the a plight of a person or group of people
2. a emotionally concerned person
(from the religous picture of the bleeding heart of jesus)
They typically hold the view that the majority are responsible for any minority plight whatsoever, and that minorities can never, ever be responsible for their own condition. They often feel that the public is obligated to make special accommodations for every group, no matter how large or small it is. They claim to be against racism, but in actuality are racist against whites, and believe that modern generations are responsible for the wrongdoings of their ancestors. They will usually pursue useless degrees with their parents' money, and they will never be found studying the hard sciences.
A bleeding heart is NOT simply any left-leaning individual. Supporting social and environmental causes does NOT make one a bleeding heart. It refers specifically to those who take the views to a ridiculous extreme, make completely illogical, unrealistic demands, and are unable to recognize their own hypocrisy.
demanding that all businesses should provide transgender restrooms = bleeding heart
supporting gresponsible environmental policies and conservation of fragile ecosystems = not bleeding heart
crying about things like deer hunting and belonging to PETA = bleeding heart
But my hands were tied.
The bleeding hearts and artists,
Let him get away with murder.
Pink Floyd, "The Trial"