|Sound change and alternation|
Paragoge (/ˌpærəˈɡoʊdʒi/; from Greek: παραγωγή additional: παρα- prefix para- 'extra', ἀγωγή agogē 'bringing in') is the addition of a sound to the end of a word. Often caused by nativization, it is a type of epenthesis, most commonly vocalic epenthesis.
Paragoge is particularly common in Brazilian Portuguese, not only in loanwords but also in word derivation. It is also present in the accents of many Brazilians while speaking foreign languages such as English.
Some languages have undergone paragoge as a sound change, and modern forms are longer than the historical forms they are derived from. Italian sono 'I am', from Latin sum, is an example. Sometimes, as above, the paragogic vowel is an echo vowel, such as Proto-Oceanic *saqat "bad" > Uneapa zaɣata.
Some languages add a sound to the end of a loanword when it would otherwise end in a forbidden sound. Some languages add a grammatical ending to the end of a loanword to make it declinable.
Paragoge can occur in the inherited words of a language as well. This is the case with many words in Romance languages.