song
noun
1 [C] a usually short piece of music with words which are sung:
to sing a song
a love/folk/pop song
See also swansong.

2 [U] the act of singing, or singing when considered generally:
He was so happy he wanted to burst/break into song (= start singing).

3 [C or U] the musical sound that a bird makes:
bird song
A thrush's song was the only sound to break the silence.

(ref-cambridge dictionaries online)