prosthesis

UK: /prɒsˈθiːsɪs/

US: /prɑsˈθisɪs/

US: (pros thē′sis for 1; pros′thə sis for 2)

Inflections of 'prosthesis' (n): npl: prostheses

WordReference Random House Learner's Dictionary of American English © 2026

pros•the•sis /prɑsˈθisɪs/   n. [countable] , pl. -ses 

1. Surgery a device that substitutes for or assists a missing or poorly functioning part of the body, as a limb.

pros•thet•ic /prɑsˈθɛtɪk/  adj. See -thes-.

WordReference Random House Unabridged Dictionary of American English © 2026

pros•the•sis  (pros thē′sis for 1; pros′thə sis for 2), n., pl. -ses 

(-sēz for 1; -sēz′ for 2). 
1. Surgery a device, either external or implanted, that substitutes for or supplements a missing or defective part of the body.
2. Phonetics [Gram., Prosody.] the addition of one or more sounds or syllables to a word or line of verse, esp. at the beginning.

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

pros•thet•ic  (pros thet′ik), adj.  pros•thet′i•cal•ly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

prosthesis / ˈprɒsθɪsɪs prɒsˈθiːsɪs/ noun ( -ses / -ˌsiːz/)

1. the replacement of a missing bodily part with an artificial substitute
2. an artificial part such as a limb, eye, or tooth
3. another word for prothesis

Etymology: 16th Century: via Late Latin from Greek: an addition, from prostithenai to add, from pros- towards + tithenai to place

prosthetic / prɒsˈθɛtɪk/ adjective

prosˈthetically adverb