"Ultrasonic" refers to sound waves with frequencies higher than the upper limit of human hearing, typically above 20 kHz. These high-frequency waves are widely used in medical imaging, industrial testing, and cleaning applications due to their ability to penetrate materials and reflect off boundaries. In medicine, ultrasound imaging provides real-time visuals of internal organs without radiation. Industrially, ultrasonic testing detects flaws in metals, while ultrasonic cleaners remove contaminants using high-frequency vibrations. Additionally, animals like bats and dolphins use ultrasonic waves for echolocation. The technology is valued for its precision, non-invasiveness, and versatility across scientific, medical, and engineering fields.