Yesterday I got the very fine cd by Willie K. (Kahalali'i), "Awihilima: Reflections." He carries some of his songs into a range which many call falsetto, but the high range is natural to traditional Hawai'ian music, and Willie K. is a fine performer of that music.

The dictionary defines falsetto as an artificial extending of the tenor range, but if it is natural and not artificial, is it falsetto?

I think the key is "artificial;" Willie K. is never artificial and I suspect some of the examples mentioned above are also not artificial. It also puts me in mind of some of the treble and countertenor singers required in renaissance choral works.