A device designed to be placed in the mouth and blown, or driven by steam or some other mechanism, to make a whistling sound.

An act of whistling.

A shrill, high-pitched sound made by whistling.

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.”

To make a similar sound by forcing air through a musical instrument or a pipe etc.

“The stream train whistled as it passed by.”

To move in such a way as to create a whistling sound.

“A bullet whistled past.”