Noise

Thunder is the sound caused by lightning. Depending upon the distance from and nature of the lightning, it can range from a long, low rumble to a sudden, loud crack. The sudden increase in temperature and hence pressure caused by the lightning produces rapid expansion of the air in the path of a lightning bolt. In turn, this expansion of air creates a sonic shock wave, often referred to as a "thunderclap" or "peal of thunder". The scientific study of thunder is known as brontology and the irrational fear (phobia) of thunder is called brontophobia.

thumb|upright|NASA researchers at [[Glenn Research Center measuring aircraft engine noise in 1967]]

thumb|Spectrograms of [[Thrush nightingale (Luscinia luscinia) and Common nightingale (Luscinia megarhynchos) singing help to reliably distinguish these two species by voice.]] Bioacoustics is a cross-disciplinary science that combines biology and acoustics. Usually, it refers to the investigation of sound production, dispersion and reception in animals (including humans). This involves neurophysiological and anatomical basis of sound production and detection, and relation of acoustic signals to the medium they disperse through. The findings provide clues about the evolution of acoustic mechan

Phonophobia, also called ligyrophobia or sonophobia, is a fear of or aversion to specific sounds—a type of specific phobia as well as a form of auditory hypersensitivity. Occasionally it is called acousticophobia. Although some sounds could be feared by most people, such as certain loud sounds or sounds that signal threats, fears of these sounds would not be considered phonophobia unless the amount of fear and anxiety was disproportionate. In phonophobia, the feared sounds may be ones that are soft and non-damaging, such as kitchen sounds or a door closing. Another example is watching someone

light created by gunfire

electric or electromagnetic acoustic phenomenon

anti-loitering device

noise encountered in the workplace

random radio noise that originates outside the Earth's atmosphere

noise pollution inside or outside an operating aircraft

unpitched, indeterminate, uncontrolled, loud, unmusical, or unwanted sound in music

synthetic background noise used to fill artificial silences in radio and wireless transmissions