adjective ダウンロード 🔗共有 超音波の (acoustics) Beyond (higher in frequency than) the range of sound perceptible to the human ear; with a frequency of 20 kilohertz or higher. Examples : "The dog whistle emits an ultrasonic sound that humans can't hear, but dogs can. " 犬笛は、人間には聞こえないが犬には聞こえる超音波を発します。 sound physics frequency technology science electronics AIとチャット語彙ゲーム読解練習