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malpractice mal·prac·tice (māl-prāk'tĭs)
Improper or negligent treatment of a patient, as by a physician, resulting in injury, damage, or loss.
Mistakes or negligent conduct by a professional person, especially a physician, that results in damage to others, such as misdiagnosis of a serious illness. Damaged parties often seek compensation by bringing malpractice suits against the offending physician or other professional.