ultrasounds

/AH0 L T R AH0 S AW1 N D Z/
noun
  1. 1

    Sound with a frequency greater than the upper limit of human hearing, which is approximately 20 kilohertz.

  2. 2

    The use of ultrasonic waves for diagnostic or therapeutic purposes.

Antonyms

Source: https://en.wiktionary.org/wiki/ultrasound, https://en.wiktionary.org/wiki/ultrasounds