1. sound waves with frequencies above the range of human hearing, typically above 20,000 Hz
Usage: technical; physics
2. medical imaging procedures that use high-frequency sound waves to create pictures of internal body structures
Usage: medical

Examples

• Bats use ultrasounds to navigate in the dark.
• The doctor ordered ultrasounds to check the baby’s development.
• Dolphins communicate using ultrasounds that humans cannot hear.
• She had several ultrasounds during her pregnancy.
• The technician performed ultrasounds on the patient’s abdomen.
• Scientists study how animals produce and detect ultrasounds.
• The ultrasounds revealed no abnormalities in the organs.