blowing air into a whistle causes air to vibrate inside the whistle
whistle is signal. whistling is blowing_to_make_tune. steam_whistle is whistle. whistle is not signal. whistle is sound. steam_whistle is not whistle. tin_whistle is not whistle. whistling is not blowing_to_make_tune. tin_whistle is not woodwind. tin_whistle is whistle.