whistle

[Dr.Appalayya]

My 19 year-old son produces whistle by contracting the cheeks and making the wind pass through the restricted opening of his mouth.

Is it also called whistle?

 

[Elwintee]

My 19 year-old son produces whistle by contracting the cheeks and making the wind pass through the restricted opening of his mouth.

Is it also called whistle?

You mean he breathes in while making the noise, rather than out? Yes, as long as the sound is the same that is a whistle too.

 

[icecreamsoldier]

As Elwintee says, whistle describes a sound, no matter how it is produced. For example a kettle, the wind and any projectile can also whistle.