acous-, acou-, acouo-, acoustico-, acouto-, acousti-, -acousia, -acousis, -acoustical, acu-, -acusis-, -acusia

(Greek: akoustikos, to hear, hearing; to listen, listening)

optoacoustic (adjective), more optoacoustic, most optoacoustic
Relating to a technique in which a beam of light passing through a gaseous medium is capable of generating sound if the beam is periodically interrupted at some characteristic sound frequency: "When Bryan was studying acoustics in his physics class, he experimented with a laser beam and was able to generate sound waves in gas by measuring the sounds that were generated by the optoacoustic effects at the frequencies of the interruptions of the light beam."
osteoacusis (s) (noun), osteoacuses (pl)
A conduction of sounds through the bones: "The test for osteoacusis is a normal part of Carol's routine annual medical hearing examination."
otacoustical (adjective) (not comparable)
A reference to an instrument used to assist better hearing; such as, an ear-trumpet: "The exhibition at the museum was presenting modern and antique otacoustical devices which were made to help the hearing impaired."
otacousticon (s) (noun), otacousticons (pl)
A device that aids hearing: "One kind of otacousticon is a hearing aid."
otoacoustic (adjective), more otoacoustic, most otoacoustic
Referring to the very faint sounds produced by the ear; thought to represent mechanical vibrations in the cochlea: "To detect otoacoustic emissions, researchers insert a miniature probe ­which looks somewhat like a hearing aid and that contains a sound source and a sensitive microphone ­into the outer ear canal."

The human ear serves as both a detector and a generator of sound. Tiny hair cells in the inner ear convert incoming acoustic vibrations into nerve signals, but as the cells move in response to sound waves, they themselves produce faint sounds, which are known as otoacoustic emissions.

By listening to these feeble signals, researchers can study in remarkable detail how the inner ear works. Now, detection of these emissions shows promise as a means of evaluating a wide range of common hearing problems involving damage to hair cells.

The sound source generates either a click or a tone, and the microphone picks up the resulting ear-generated sound. In an ear with normal hearing, the faint output sound is nearly identical to the input sound.

This type of test may prove particularly valuable because many hearing difficulties involve damage to hair cells. Such damage can be caused by exposure to prolonged or excessively loud noises, various drugs, or bacterial and viral infections.

—Compiled from information located in
Science News by Brenda Lonsbury-Martin;
University of Miami (Florida) Ear Institute;
February 27, 1993; page 141.
oxyacusis (s) (noun), oxyacuses (pl)
An abnormal sensitivity to sounds, sometimes found in hysteria, in which hearing is abnormally acute: "Dr. Ashton's patient often felt like screaming because the oxyacusis that he was experiencing was so painful."
paracusia, paracousia (s) (noun); paracusias, paracousias (pl)
Any kind of abnormal hearing: "For her internship program at the hospital, Dr. Lennox participated in the audiology program, studying all aspects of paracusia before deciding on a specialization."
paracusis, paracousis (s) (noun); paracusies, paracouses (pl)
Hearing loss which may be associated with inaccurate perception of pitch: "Because of the paracusis which Iris was experiencing, she found it difficult to modulate her voice when speaking because she could not accurately hear the pitch of her own voice."
polyacoustic (adjective), more polyacoustic, most polyacoustic
Referring to the process of multiplying or magnifying sounds: "The new amplifiers were the top of the line, the most polyacoustic equipment that the stadium could find."
polyacoustics (pl) (noun) (a plural used as a singular)
The art of magnifying sounds: "The sound engineer at the outdoor concert venue was trained in polyacoustics and he was able to ensure that the amplification equipment was working properly."
presbycusis [presbyacusia] (s) (noun), presbycuses (pl)
Dullness of hearing, which is a characteristic of old age, including the loss of the ability to perceive or to discriminate sounds: "A person's presbycusis usually occurs progressively as he or she ages."

"Symptoms of presbycusis are gradual hearing loss and tinnitus."

"The normal process of aging produces changes in the cochlea and the cochlear nerves; in other words, damage in the inner ear, and results in permanent sensorineural hearing loss."

"Presbycusis most often occurs in both ears and because the loss of hearing is so gradual, people with presbycusis may not realize that their hearing is diminishing."

Presbycusis is common, affecting a third of people between 65 and 75 years and up to a half of people 75 and over."

"The only treatment for presbycusis is the wearing of hearing aids which can be worn in the ears or behind the ears."

"Other visual communicative technique; such as, lipreading or watching facial expressions are also helpful in coping with hearing loss."

—Primarily compiled from information in
The Consumer's Medical Desk Reference; by Charles B. Inlander
and the Staff of the People's Medical Society;
The Stonesong Press, Inc.; New York; 1995; page 99.
pseudacousma, pseudoacousma (s) (noun); pseudacousmas, pseudoacousmas (pl)
A subjective or imaginary sensation as if sounds are altered in pitch and quality: "Pete became hesitant to talk in public because of his pseudacousma which made him uncertain about how his voice would be heard by others."

"The poor acoustics of the auditorium resulted in the symphony conductor's concern that she might be experiencing pseudoacousma."

pseudacusis (s) (noun), pseudacuses (pl)
Hearing sounds that don't exist; false hearing: "Irene was awakened in the night by a loud noise, but it turned out to be an experience of pseudacusis, so she went back to sleep after she checked to be sure the windows and doors were secured."
Psittacousaurid
A family of “parrot lizards.”
psychoacoustical (adjective), more psychoacoustical, most psychoacoustical
A reference to the study of the relationship between the perceptions of sounds and their physiological and psychological effects on people: "Scientists are discovering that some psychoacoustical sounds cause hearing loss that is often misdiagnosed as an effect of aging."

If you would like to take a self-scoring quiz over many of the words in this unit, then click on this Hearing Quiz link so you can see how much you know about some of these “acous-, acou-” words.

Related "hear, hearing; listen, listening" units: audio-; ausculto-.