Pronunciation IPA (key): /prɒsˈθiːsɪs/ or /ˈprɒsθɪˌsɪs/ Audio (US)(file) Noun Singular prosthesis Plural prostheses (countable) (medicine) A prosthesis is an artificial body part. Related words prostheticWikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads