An aria is a rhythmical melody, as distinct from recitative. The term was originally applied to a measured lyrical piece either for one or several voices. However, it is now commonly applied to a song inroduced in a cantato, oratorio, or opera, and intended for one voice supported by instruments.
The "aria grande" has taken many forms, mostly of two classes – the aria with "da capo", in which the first section is repeated in extenso after the second or intermediary one, and the aria without "da capo", a more varied and extended form, in which the first section may be repeated several times, and the last time generally more or less expanded into a coda.
An arietta is a short melody.