Definition from Wiktionary, the free dictionary
Alternative forms 
bloodsucker (plural bloodsuckers)
- One who drinks the blood of others, especially by sucking blood through a puncture wound; a hemovore.
- By extension, any parasite.
- By extension, one who attempts to take as much from others as possible.
- A vampire.
one who drinks the blood of others
parasite — see parasite
one who attempts to take as much from others as possible
vampire — see vampire