whistling

fe’l verb

1. To make a shrill, high-pitched sound by forcing air through the mouth. To produce a whistling sound, restrictions to the flow of air are created using the teeth, tongue and lips. Never whistle at a funeral.
2. To make a similar sound by forcing air through a musical instrument or a pipe etc. The stream train whistled as it passed by.
3. To move in such a way as to create a whistling sound. A bullet whistled past.
4. To send, signal, or call by a whistle.

ot noun

1. A shrill, breathy sound; a whistle.