proth·​e·​sis ˈprä-thə-səs How to pronounce prothesis (audio)
plural protheses ˈprä-thə-ˌsēz How to pronounce prothesis (audio)
: the addition of a sound to the beginning of a word (as in Old French estat—whence English estate—from Latin status)
prothetic adjective

Word History


Late Latin, alteration of prosthesis, from Greek, literally, addition — more at prosthesis

First Known Use

circa 1550, in the meaning defined above

Time Traveler
The first known use of prothesis was circa 1550

Dictionary Entries Near prothesis

Cite this Entry

“Prothesis.” Dictionary, Merriam-Webster, Accessed 21 Jul. 2024.

Medical Definition


proth·​e·​sis ˈpräth-ə-səs How to pronounce prothesis (audio)
plural protheses -ˌsēz How to pronounce prothesis (audio)
prothetic adjective

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