Ultrasound
Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is no different from ‘normal’ (audible) sound in its physical properties, except in that humans cannot hear it. This limit varies from person to person and is approximately 20 kilohertz (20,000 hertz) in healthy, young adults. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz.
Ultrasound is used in many different fields. Ultrasonic devices are used to detect objects and measure distances. Ultrasound imaging or sonography is often used in medicine. In the nondestructive testing of products and structures, ultrasound is used to detect invisible flaws. Industrially, ultrasound is used for cleaning, mixing, and to accelerate chemical processes. Animals such as bats and porpoises use ultrasound for locating prey and obstacles. Scientist are also studying ultrasound using graphene diaphragms as a method of communication.
Ultrasound (noun)
Sound with a frequency greater than the upper limit of human hearing, which is approximately 20 kilohertz.
Ultrasound (noun)
The use of ultrasonic waves for diagnostic or therapeutic purposes.
Ultrasound (verb)
To treat with ultrasound.
Ultrasonic (adjective)
Beyond (higher in frequency than) the range of sound perceptible to the human ear; with a frequency of 20 kilohertz or higher.
Ultrasound (noun)
sound or other vibrations having an ultrasonic frequency, particularly as used in medical imaging
“an ultrasound scanner”
Ultrasound (noun)
an ultrasound scan, especially one of a pregnant woman to examine the fetus
“I have to take my daughter-in-law for her ultrasound”
Ultrasonic (adjective)
of or involving sound waves with a frequency above the upper limit of human hearing.