Prothesis (linguistics)

In linguistics, prothesis (/ˈprɒθəsɪs/; from post-classical Latin based on Ancient Greek πρόθεσις próthesis 'placing before'), or less commonlyprosthesis (from Ancient Greek πρόσθεσις prósthesis 'addition') is the addition of a sound or syllable at the beginning of a word without changing the word's meaning or the rest of its structure. A vowel or consonant added by prosthesis is called prothetic or prosthetic.

Prothesis is different from the adding of a prefix, which changes the meaning of a word.

Prothesis is a metaplasm, a change in spelling or pronunciation. The opposite process, the loss of a sound from the beginning of a word, is called apheresis or aphesis.

Prothesis may be a way of word formation during borrowing from foreign languages or during derivation from protolanguages.

A well-known example is that /s/ + stop clusters (known as s impurum), in Latin, gained a preceding /e/ in early Romance languages (Old Spanish, Old French).

Thus, Latin status changed to Spanish and French / (in which the s was lost) "state"/"been", and Latin speciālis changed to Spanish and Old French especial (Modern French spécial, and English special).

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