Glossary
Searchable terminology from accessibility, web standards, and related fields.
40 results found in Conditions.
- Partial Trisomy 9p (9p Duplication Syndrome, Rethore Syndrome)
- A rare chromosomal condition in which a portion of the short arm of chromosome 9 is present in triplicate rather than in duplicate. The condition is associated with intellectual disability, distinctiv…
- People with Dementia (PwD)
- A person-first term used in accessibility and dementia research to refer to individuals living with dementia — an umbrella term covering progressive neurological conditions (such as Alzheimer's diseas…
- People with Severe Motor Disabilities (PSMD)
- A term used in assistive technology and human-robot interaction research to describe individuals whose motor impairments are severe enough that they cannot reliably use their hands or arms for everyda…
- Postlingual Deafness (Postlingually Deaf, Acquired Hearing Loss)
- Hearing loss that occurs after a person has acquired spoken language, typically after about age three to five. Postlingually deaf people usually retain spoken-language fluency, literacy, and memory of…
- Prelingual Deafness (Prelingually Deaf, Congenital Deafness)
- Deafness present at birth or acquired before a child has developed spoken language, typically before around age three. Prelingually deaf individuals commonly learn a signed language as a first languag…
- Presbyopia (Age-Related Farsightedness)
- An age-related vision condition where the eye gradually loses its ability to focus on nearby objects, typically becoming noticeable in the early to mid-40s. Presbyopia affects virtually everyone as th…
- Protanomaly (Protan Anomalous Trichromacy)
- A type of colour vision deficiency where the long-wavelength (red) cone cells have a shifted sensitivity range rather than being absent entirely. Protanomaly is a milder form of protan CVD compared to…
- Protanopia (Protan Dichromacy, Red-Blind)
- A type of colour vision deficiency caused by the complete absence of long-wavelength (red) cone cells in the retina. People with protanopia cannot distinguish between red and green and perceive reds a…
- Rett Syndrome (RTT)
- A rare, X-linked neurodevelopmental disorder caused in most cases by mutations in the MECP2 gene, affecting almost exclusively females. After typical early development, children with Rett syndrome los…
- Scoliosis
- A structural condition in which the spine develops a sideways curvature, often in an 'S' or 'C' shape. Scoliosis ranges from mild curves requiring only monitoring to severe cases that can affect postu…
- Sensorineural Hearing Loss (SNHL, Nerve Deafness)
- Sensorineural hearing loss is hearing loss caused by damage to the hair cells of the inner ear (cochlea) or the auditory nerve, in contrast to conductive hearing loss, which involves the outer or midd…
- Sensory Processing Sensitivity (SPS, Sensory Processing Differences)
- Sensory Processing Sensitivity refers to differences in how an individual perceives, filters, and responds to sensory input across modalities such as vision, sound, touch, taste, and proprioception. I…
- Sloping Hearing Loss (High-frequency Hearing Loss, Sloping SNHL)
- Sloping hearing loss is a common audiogram shape in which hearing thresholds are relatively preserved at low frequencies and progressively worse at higher frequencies, producing a downward slope on th…
- Social Anxiety (Social Anxiety Disorder, Social Phobia)
- Social anxiety (social anxiety disorder, SAD) is a mental-health condition characterised by persistent and intense fear of being judged, rejected or humiliated in social or performance situations, lea…
- Spasmodic Dysphonia (Laryngeal Dystonia, SD)
- Spasmodic dysphonia is a neurological voice disorder characterized by involuntary spasms of the laryngeal muscles during speech, causing interruptions in voice production. The most common form, adduct…
- Tinnitus (Ringing in the Ears)
- Tinnitus is the perception of sound - most commonly ringing, buzzing, or hissing - without a corresponding external source. It can be continuous or intermittent, uni- or bilateral, and ranges from mil…
- Tritanomaly (Tritan Anomalous Trichromacy)
- A rare type of colour vision deficiency where the short-wavelength (blue) cone cells have a shifted sensitivity range. Tritanomaly results in reduced ability to distinguish blue from yellow. It is the…
- Tritanopia (Tritan Dichromacy, Blue-Blind)
- A rare type of colour vision deficiency caused by the complete absence of short-wavelength (blue) cone cells in the retina. People with tritanopia have difficulty distinguishing blue from yellow and b…
- Tunnel Vision (Peripheral Vision Loss, PVL)
- A visual impairment characterized by the loss of peripheral vision while central vision may remain intact, resulting in a narrow field of view as if looking through a tunnel. Tunnel vision can be caus…
- Vision Impairment (Visual Impairment, VI)
- An umbrella term for any reduction in visual function — including low vision, blindness, and functional limitations that affect everyday tasks — regardless of cause. The World Health Organization dist…