Paragoge (/ˌpærəˈɡoʊdʒi/; from Greek: παραγωγή; adj. paragogic /ˌpærəˈɡɒdʒɪk/), 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 most accents of Brazilians who speak 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.
Some languages add a sound to the end of a loanword when it would otherwise end in a forbidden sound. Similarly, some languages add a sound to the end of a loanword to make it declinable.