The offspring of a vampire and a human, a dhampir is generally portrayed as one with all or most powers of a vampire, with few to no disadvantages. This is sometimes reversed, depending on the context and writer.
In mythology, dhampirs often rejected their vampire blood and became extremely successful vampire hunters due to their advanced abilities. However, despite their help to the human race, they were continually rejected nonetheless because of their vampire blood. Thus, dhampirs most always spent their life as nomads, rejected by both humans and vampires--vampires due to weakness, humans due to fear of the dhampirs' strength.
This word was horribly butchered in the Vampire Hunter D movies, as the translation from the Japanese pronunciation 'danpuru' back to English spawned the word dunpeal.
Cursed to a life of solitude due to his being a dhampir, D rejected his name and adopted his pseudonym so he would not be associated with his cursed "father", the infamous Dracula.