bleeder

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1. A person, such as a hemophiliac, who bleeds freely or is subject to frequent hemorrhages.
2. 1. Slang. A blood vessel from which there is uncontrolled bleeding.
   2. A blood vessel severed by trauma or surgery that requires cautery or ligature to arrest the flow of blood.
3. A person who draws blood from another; a phlebotomist.

A small valve used to drain fluid from a pipe, radiator, vessel, etc.

1. A person, such as a hemophiliac, who bleeds freely or is subject to frequent hemorrhages.
2. A blood vessel from which there is uncontrolled bleeding.
3. A blood vessel severed by trauma or surgery that requires cautery or ligature to arrest the flow of blood.
4. A person who draws blood from another; a phlebotomist.

1. the popular term for an animal who bleeds freely, especially one suffering from a condition in which the blood fails to clot properly such as in hemophilia. In horses the term means one which bleeds from the nostrils during a race. Such horses are not allowed to participate in races. See also epistaxis.
2. any large blood vessel cut during surgery.

The noun has one meaning:

Meaning #1: someone who has hemophilia and is subject to uncontrollable bleeding
  Synonyms: hemophiliac, haemophiliac, hemophile, haemophile