ultrasonography

Diagnostic imaging in which ultrasound is used to image an internal body structure or a developing fetus. See Note at ultrasound.

An imaging technology that uses high-frequency sound waves to visualize underwater objects, topography, boundaries between layers, and currents. It is often used to locate underwater vehicles on the ocean floor. The sound waves are broadcast, and the timing and frequency shift of their echoes are analyzed in much the same manner as in sonar to produce an image or map of the phenomena or objects under investigation. Also called ultrasound.