whistle
n. countablen. a small tool that makes a high, loud sound when you blow air through it. It can also mean the sound you make by blowing air through your lips.
n. an instrument used to produce a shrill, high-pitched sound by means of a forced breath; also, the sound itself produced by such an instrument or by the lips.
The referee blew his whistle to end the game.
The train gave a long, loud whistle as it pulled out of the station and headed north.
The sudden, piercing whistle of the kettle interrupted their conversation, signaling that the water had finally reached a rolling boil.
From Middle English whistel, whistil, whistle, from Old English hwistle, from the verb (see below).
From Middle English whistlen, from Old English hwistlan, hwistlian (“to whistle”), from Proto-West Germanic hwistlōn, from Proto-Germanic hwistlōną (“to make a hissing sound”). Cognate with Swedish vissla (“to whistle”), Icelandic hvísla (“to whisper”), Russian свистеть (svistetʹ, “to whistle”).
Often used with the verb 'blow'.