prosthesis

American  

[pros-thee-sis, pros-thuh-sis] / prɒsˈθi sɪs, ˈprɒs θə sɪs /

noun

plural

prostheses

1. a device, either external or implanted, that substitutes for or supplements a missing or defective part of the body.

2. Grammar, Prosody. the addition of one or more sounds or syllables to a word or line of verse, especially at the beginning.

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prosthesis British  

/ ˈprɒsθɪsɪs, prɒsˈθiːsɪs, prɒsˈθɛtɪk /

noun

1. surgery

   1. the replacement of a missing bodily part with an artificial substitute

   2. an artificial part such as a limb, eye, or tooth

2. linguistics another word for prothesis

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prosthesis Scientific  

/ prŏs-thē′sĭs /

plural

prostheses

1. An artificial device used to replace a missing or defective body part, such as a limb or a heart valve.

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Other Word Forms

• prosthetic
  adjective
• prosthetically
  adverb

Etymology

Origin of prosthesis

1545–55; < Late Latin < Greek prósthesis a putting to, addition, equivalent to prós to + thésis a placing; see thesis

Explanation

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."

Example Sentences

He later said he was fortunate to not have a prosthesis.

From The Wall Street Journal • Mar. 28, 2026

She also has a white prosthesis in the place of one leg.

From Salon • Sep. 26, 2025

Vázquez continued to have problems with his right eye, which required seven surgeries and was eventually removed in 2016 and replaced with a prosthesis.

From Los Angeles Times • Dec. 3, 2024

Rehm, who lost his right leg below the knee in a wakeboarding accident in 2003 and jumps using a bladed prosthesis, has been the star of Para-athletics, constantly pushing the boundaries of his event.

From BBC • Aug. 25, 2024

“No matter how good the prosthesis is, if the mind isn’t willing, the leg won’t work. With you I know I don’t have to worry about that.”

From "The Running Dream" by Wendelin Van Draanen