Glossary
Searchable terminology from accessibility, web standards, and related fields.
68 results found in Conditions and Disabilities.
- Developmental Apraxia of Speech (Childhood Apraxia of Speech, CAS, DAS, Verbal Dyspraxia)
- A motor speech disorder in which children have difficulty planning and coordinating the movements needed for speech, despite having no muscle weakness. Children with developmental apraxia of speech kn…
- Developmental Delay (Developmental Disability, Global Developmental Delay)
- A condition in which a child does not reach developmental milestones — such as motor skills, speech, social skills, or cognitive abilities — at the expected ages. Developmental delay may affect one or…
- Dichromat (Dichromacy, Dichromatic Vision)
- A person with colour vision based on only two types of functional cone cells in the retina instead of the typical three, resulting in a reduced ability to distinguish certain colours. Dichromats perce…
- Distractibility (Attentional Distractibility, Susceptibility to Distraction)
- A cognitive characteristic in which a person has difficulty maintaining focus on a task due to sensitivity to irrelevant stimuli in their environment. Distractibility is a feature of many conditions i…
- Down Syndrome (Trisomy 21)
- A genetic condition caused by the presence of an extra copy of chromosome 21, resulting in varying degrees of intellectual and developmental differences. People with Down Syndrome may experience chall…
- Fetal Alcohol Spectrum Disorder (FASD, Fetal Alcohol Syndrome, FAS)
- A group of conditions that can occur in a person whose mother consumed alcohol during pregnancy. Effects can include physical, behavioral, and learning problems, with a wide range of severity. FASD is…
- Fine Motor Skills (Fine Motor Control, Dexterity)
- The ability to make precise, coordinated movements using the small muscles of the hands, fingers, and wrists. Fine motor skills are essential for tasks such as typing, using a mouse, performing touch …
- Freezing of Gait (FOG, Gait Freezing, Motor Blocks)
- A common and debilitating symptom of Parkinson's Disease in which a person suddenly and temporarily feels as though their feet are glued to the floor, despite intending to walk. Freezing episodes typi…
- Hyperopia (Farsightedness, Long-Sightedness, Hypermetropia)
- A refractive error in which the eye focuses light behind the retina rather than on it, causing near objects to appear blurred while distant objects may remain relatively clear. Hyperopia occurs when t…
- Intellectual Disability (ID, Learning Disability (UK), Cognitive Disability, Developmental Disability)
- A condition characterized by significant limitations in both intellectual functioning (reasoning, learning, problem-solving) and adaptive behavior (conceptual, social, and practical skills) that origi…
- Keratoconus
- A progressive eye condition in which the normally round cornea thins and bulges into a cone-like shape, causing irregular astigmatism and significant visual distortion that cannot be fully corrected w…
- Language-Based Learning Impairment (LLI, Language Learning Impairment, Language Learning Disability)
- A developmental condition in which children have difficulty acquiring language and later reading skills while other cognitive abilities appear relatively intact. Language-based learning impairments af…
- Leber Hereditary Optic Neuropathy (LHON)
- A maternally inherited genetic condition that causes sudden or rapid loss of central vision, typically affecting young adults between the ages of 15 and 35. LHON results from mutations in mitochondria…
- Low-Functioning Autism (LFA, Classic Autism, Level 3 Autism)
- A descriptor historically used to characterize individuals with autism spectrum disorder who have significant support needs, including limited or no verbal communication, intellectual disability, and …
- Mathematics Learning Disability (Math Disability, Mathematical Disability, Mathematics Disorder)
- A specific learning disability that affects a person's ability to understand, learn, or perform mathematical operations. Mathematics learning disabilities can manifest as difficulty with number sense,…
- Meares-Irlen Syndrome (Irlen Syndrome, Visual Stress Syndrome, Scotopic Sensitivity Syndrome)
- Meares-Irlen Syndrome is a perceptual processing disorder that affects how the brain processes visual information, causing symptoms of visual stress including pattern glare, perceptual distortions, ey…
- Memory Impairment (Memory Loss, Memory Deficit)
- A reduction in the ability to encode, store, or retrieve information, ranging from mild forgetfulness associated with normal ageing to severe deficits caused by conditions such as dementia or traumati…
- Myopia (Nearsightedness, Short-Sightedness)
- A common refractive error in which the eye focuses light in front of the retina rather than on it, causing distant objects to appear blurred while near objects remain clear. Myopia occurs when the eye…
- Neurodevelopmental Disorders (NDD, Neurodevelopmental Disabilities)
- A group of conditions that originate during the developmental period and are characterized by impairments in personal, social, academic, or occupational functioning. Neurodevelopmental disorders inclu…
- Neuromuscular Disease (Neuromuscular Disorder, NMD)
- A broad category of conditions that affect the nerves controlling voluntary muscles, the muscles themselves, or the communication between nerves and muscles. Neuromuscular diseases include muscular dy…