In medicine, a prosthesis is an artificial body part meant to replace one that's missing. If you were born with only one arm, doctors might fit you with a prosthesis to fill in for your missing arm.

When someone loses a body part because of illness or an accident (or if they're born without a limb or another body part), they sometimes have the option to get a prosthesis. Some prostheses are very simple duplicates of the absent part, while others are extremely complex devices. Some limb prostheses are even "robotic," allowing their users to move them as if they were real. In Greek, prosthesis means "addition."

Definitions of prosthesis
  1. noun
    corrective consisting of a replacement for a part of the body
    synonyms: prosthetic device
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    glass eye
    prosthesis consisting of an artificial eye made of glass
    a prosthesis placed permanently in tissue
    a prosthesis used to close an opening (as to close an opening of the hard palate in cases of cleft palate)
    leg, peg, pegleg, wooden leg
    a prosthesis that replaces a missing leg
    artificial heart
    a pump that replaces the natural heart
    artificial joint
    a metal or plastic part that is surgically implanted to replace a natural joint (possibly elbow or wrist but usually hip or knee)
    breast implant
    an implant for cosmetic purposes to replace a breast that has been surgically removed
    dental implant
    an implant that replaces a natural tooth
    heart valve
    an implant that replaces a natural cardiac valve
    IOL, interocular lens implant, lens implant
    a clear plastic lens that is implanted in the eye; usually done when the natural lens has been removed in a cataract operation
    penile implant
    an implant that creates an artificial erection
    implant consisting of a tube made of plastic or rubber; for draining fluids within the body
    type of:
    corrective, restorative
    a device for treating injury or disease
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