Prothesis (linguistics)

In linguistics, prothesis (/ˈprɒθɪsɪs/; from post-classical Latin based on Ancient Greek: πρόθεσις próthesis 'placing before'), or less commonly prosthesis (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 prothesis is called prothetic or less commonly 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 occur during word formation from borrowing from foreign languages or the derivation from protolanguages.

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

Thus, Latin status changed to Spanish estado and French état, été (in which the s was later lost) "state"/"been", and Latin speciālis changed to Spanish and Old French especial (Modern French spécial and Italian speciale).

Some Turkic languages avoid certain combinations of consonants at the beginning of a word. In Turkish, for instance, Smyrna is called İzmir, and the word station, borrowed from French, becomes Turkish istasyon.

Similarly, in Bashkir, a prosthetic vowel is added to Russian loanwords if a consonant or a consonant cluster appears at the beginning: арыш "rye" from Russian рожь, өҫтәл "table" from Russian стол, эскәмйә "bench" from Russian скамья, etc.