infrasound
/ˈin-frə-ˌsau̇nd/ (ame, mw)
infrasound — noun
1. Sound that exists as pressure waves at frequencies too low for the human ear to
Sound that exists as pressure waves at frequencies too low for the human ear to detect, typically below about 20 hertz, though it can sometimes be felt as a physical vibration rather than heard.
Hassan learned that elephants use infrasound to communicate across distances of up to ten kilometres.
use infrasound to communicate [across distance]
The volcano monitoring station detected strong infrasound signals three hours before the eruption.
detect infrasound signals from [natural source]
Residents near the wind farm blamed the infrasound from the turbines for their headaches.
Qing's research team placed infrasound sensors along the coast to track approaching tsunami waves.
The cinema installed special panels to reduce infrasound leakage into neighbouring rooms.
- low-frequency sound
more general term that can include audible low frequencies as well as those below the hearing range
- sub-audible sound
less common; emphasises that the sound cannot be heard, whereas infrasound is defined by frequency range
- ultrasound
sound waves at frequencies above the human hearing range, typically above 20,000 hertz
文法句型
infrasound + noun (infrasound waves / infrasound signals)
detect / produce / generate + infrasound
用法筆記
Frequently used as an attributive noun before another noun (e.g. infrasound waves, infrasound detection). Contrast with ultrasound, which refers to frequencies above the human hearing range. Infrasound is uncountable in standard scientific writing — use 'an infrasound signal' or 'a type of infrasound' rather than 'an infrasound' when a countable expression is needed.