Glossary beginning with A

Click one of the letters above to go to the page of all terms beginning with that letter.


acoustic anthropocene

"The impact of people on natural soundscapes must have grown gradually with the human population growth on earth and the use of stones and metal for construction and tool making in the Stone, Bronze and Iron Ages. High-intensity anthropogenic sound events may have emerged with the invention of gunpowder in China, in the 9th century, used for mining, warfare and demolition. However, the invention of the steam engine, and the industrial revolution in general, by the end of the 18th century, can be regarded as the real start of steady growth of industrial and traffic noise in the western world. The automotive industry rose in the USA by the end of the 19th century and a considerable acceleration in car production happened soon after World War II, in which period commercial aviation also started to grow rapidly. Growth in noise pollution levels in the oceans roughly coincided with that in air, and was primarily related to the cold war increase of sonar use and the steady incline in global shipping activity associated with international trade. Seismic exploration for geophysical surveys started about 90 years ago, while pile driving for wind turbines at sea in coastal areas is a recent growth sector of the last decade." [1]


acoustic aposematism

"The use of an acoustic signal by the prey to warn predators of their unpalability." [57591[/bib]

acoustic climate change

"Should we speak about 'acoustic climate change'? Due to the global nature of spread and taxonomically wide impact of noise pollution, it seems indeed reasonable to speak about acoustic climate change. Sound impact has typically been studied for a single source type and a single species. However, animals are often exposed to multiple noisy activities at the same time or in sequence, potentially in parallel with other disturbing factors such as changes in temperature regimes, drought, salinity, or invasive species. Investigating cumulative effects of different stressors will therefore be critical for our understanding of the ecological consequences of noise pollution and to come up with efficient measures for potential mitigation.We better treat noise pollution, like global warming, as an integral part of the global threat of human-induced climate change." [1]


acoustic fovea

"An area of high sensitivity to a specific, narrow range of frequencies in the auditory pathway."[1]


acoustic glints

"Changes in the amplitude and frequency in the echoes of bat calls from flapping insect wings perceived by the bat as amplitude and frequency glins against the constant echo from the background clutter." [1]


acoustic startle response

"A change in behaviour, usually involving a cessation of activity, in response to acoustic stimuli produced by a predator." [1]


active space

"The active space of a signal is the area over which the signal is perceived by the receiver. We normally consider the active space of a signal, but we can also consider the active space of different signal components." [1]


active time

"Is the female able to remember a call over that silent interval, and if so, does call complexity influence for how long the call is remembered—what we refer to as the call’s active time?" [1]



"Sound frequencies outside the range of frequencies under consideration." [1]



"The maximum deviation of an oscillation (e.g. a sound wave) from its mean value. The amplitude of audible sound waves is perceieved by human ears as the loudness of the sound." [1]


amplitude modulation

"Periodic modulation of a carrier frequency so that the carrier frequency remains unchanged and the amplitude fluctuates." [1]


analogue recorder

"An instrument for making analogue recordings of sound." [1]


analogue recording

"(on magnetic tape) A recording in which the sound is represented by a continuously variable magnetic charge (as opposed to a digital recording)." [1]



See anthropophony.

"The term used originally was anthrophony, meant to specify human-generated sound as a component of the soundscape. It is a word that we have been using, incorrectly, since the early 2000s. Only recently, while giving talks in France during the summer of 2014, was it pointed out to me by our French hosts in Quimper (Pierre Mens-Pégail) and Paris (Jérôme Sueur) taht the Greek prefix anthro meant cave, and not human, as we mistakenly assumed. Since we were not adressing the sounds that caves produce, in order to correct the term we needed to add a 'po' and modify the spelling to anthropophony." [1]


  1. Krause BL. Voices of the Wild. Yale University Press; 2015.

Synonyms: anthropophony

anthropogenic noise

"Noise pollution refers to the elevation of natural ambient noise levels due to sound-generating human activities, which may have detrimental consequences for humans and animals alike. Sounds of this kind are often referred to as anthropogenic noise. Some of these sounds are deliberate and wanted, such as music, sirens, seismic survey sounds or military sonar. Most anthropogenic noise, however, is an unwanted by-product, such as traffic or generator noise, and impulsive sounds from pile driving and explosives." [1]



"all of the sounds we humans generate. Some of these are controlled, like usic, language or theatre. But most of what humans produce is chaotic or incoherent - sometimes referred to as noise." [1]


  1. Krause BL. Voices of the Wild. Yale University Press; 2015.

"A visual record of the frequency spectrum of a sound on a time-scale (obtained form an audiospectrograph)." [1]



"Equipment for producing an audiospectrogram." [1]


auditory organ

An organ used by an organism for hearing.

"An insect will be said to hear when it is demonstrably responsive to sound. An auditory organ is one which can be shown to mediate the above response or which can itself be shown by more direct means to respond to sound." [1]


  1. Pumphrey RJ. Hearing in Insects. Biological Reviews. 1940;15(1):107 - 132. Available at:

"A flap sometimes partly concealing the tympanum." [1]


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Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith