Definify.com

Webster 1913 Edition

Noun.

(Med.)

(a)

One who, or that which, draws blood.

(b)

One in whom slight wounds give rise to profuse or uncontrollable bleeding.

bleeder ‎(plural bleeders)

A person who is easily made to bleed, or who bleeds in unusually large amounts, particularly a hemophiliac.
(surgery) A blood vessel that requires cauterization etc. to stop it from bleeding during surgery.
- 2013, Theresa Welch Fossum, Small Animal Surgery Textbook
  Ligate or cauterize small subcutaneous bleeders and identify the linea alba.
Anything that saps a resource produced by something else.
A valve designed to release a small amount of excess pressure from a system.
(Britain, slang, derogatory) A troublesome fellow; a blighter.

person who is easily made to bleed