What does aria mean?
The definition of aria
A”ri*a, n.
Etym: [It., fr. L. aër. See Air.] (Mus.)

An air or song; a melody; a tune.

Note: The Italian term is now mostly used for the more elaborate accompanied melodies sung by a single voice, in operas, oratorios, cantatas, anthems, etc., and not so much for simple airs or tunes.