Originally an air; a song; a tune; sung by a single voice with or without accompaniment. Now taken to mean a lyric song for solo voice generally having two contrasting parts (I and II), ending with a literal or elaborated repeat of part I. <br><br>The aria first developed into this form in the early operas. The arias found in an opera, cantata or oratorio usually express intense emotion. The word is used in particular to indicate formally constructed songs in opera. The so-called da capo aria of later baroque opera, oratorio and other vocal compositions, is an aria in which the first section is repeated, usually with additional and varied ornamentation, after the first two sections. <br><br>The diminutive arietta indicates a little aria, while arioso refers to a freer form of aria, like vocal writing.<br>