Universal Design Glossary: 100 Essential Terms Defined

Universal design draws vocabulary from architecture, technology, disability rights, education, and human factors engineering. This glossary provides clear definitions for the most important terms you will encounter in the field, organized alphabetically.

A

Accessible design — Design that meets specific standards ensuring usability by people with disabilities. Compare with universal design and inclusive design.

Accommodations — Modifications or adjustments made to enable a person with a disability to participate. Universal design aims to minimize the need for accommodations.

ADA — Americans with Disabilities Act (1990). U.S. civil rights law prohibiting disability discrimination.

Adaptive technology — Technology modified or specifically designed for people with disabilities. Overlaps with assistive technology.

Alt text — Alternative text that describes an image for screen reader users. Required by WCAG success criterion 1.1.1.

ARIA — Accessible Rich Internet Applications. A W3C specification that defines HTML attributes to improve web accessibility for dynamic content.

Assistive technology (AT) — Any device or software that helps people with disabilities perform tasks. Examples: screen readers, switch access devices, hearing aids, wheelchairs.

B-C

Barrier-free design — An earlier term for removing physical obstacles for people with disabilities. Predecessor to universal design.

Braille — A tactile writing system used by blind and visually impaired people. Named for Louis Braille (1809-1852).

CAPTCHA — “Completely Automated Public Turing test to tell Computers and Humans Apart.” Accessibility barrier when only visual; accessible alternatives include audio CAPTCHA and logic puzzles.

Captioning — Text display of spoken dialogue and sound effects in video content. Open captions are always visible; closed captions can be toggled.

CAST — Center for Applied Special Technology. Developer of the Universal Design for Learning framework.

Cognitive accessibility — Designing for users with cognitive, intellectual, and learning disabilities. See cognitive accessibility fundamentals.

Color blindness — Impaired ability to distinguish certain colors. Affects approximately 8% of men. Also called color vision deficiency.

Contrast ratio — The relative luminance difference between foreground and background. WCAG requires minimum 4.5:1 for normal text.

CRPD — UN Convention on the Rights of Persons with Disabilities (2006).

Curb cut effect — The phenomenon where accessible features benefit broader populations. Named for sidewalk curb cuts.

D-F

Design for All — European term equivalent to universal design. Used in EN 17161.

Disability — Under the social model, the social barriers imposed on people with impairments. See social model vs. medical model.

Dyslexia — A learning disability affecting reading and related language-based processing skills.

EAA — European Accessibility Act (Directive 2019/882).

EN 17161 — European standard for integrating universal design into organizational processes.

EN 301 549 — European standard for ICT accessibility requirements.

Equitable use — First principle of universal design. See equitable use.

Ergonomics — The study of designing equipment and environments to fit human bodies and cognitive abilities.

Focus indicator — A visible outline around the currently focused element, essential for keyboard navigation.

G-I

GAAD — Global Accessibility Awareness Day. Held annually on the third Thursday of May.

Haptic feedback — Information communicated through touch, such as vibration patterns on a smartphone.

Hearing loop — An assistive listening system that transmits audio directly to hearing aids via electromagnetic induction.

IAAP — International Association of Accessibility Professionals. Offers CPACC, WAS, and CPABE certifications.

ICF — International Classification of Functioning, Disability and Health. WHO framework integrating medical and social models.

Impairment — A physical, sensory, or cognitive condition of the body or mind. Distinguished from disability in the social model.

Inclusive design — A design methodology that considers the full range of human diversity and involves excluded communities in the design process.

Independent living — The philosophy that people with disabilities should have the same choices and control over their lives as non-disabled people.

K-N

Keyboard accessibility — The ability to operate all interface functions using a keyboard alone. WCAG success criterion 2.1.1.

Legibility — The ease with which individual characters or text can be read. Affected by font, size, contrast, and spacing.

Lever handle — A door handle operated by pushing down rather than gripping and turning. A universal design standard.

Low vision — Visual impairment not correctable by glasses. Includes conditions like macular degeneration and glaucoma.

Motor disability — Conditions affecting physical movement, strength, and coordination. See motor accessibility basics.

Neurodiversity — The concept that neurological differences are natural human variations. See neurodiversity and design.

O-R

Plain language — Communication that is clear and understandable to the intended audience on the first reading.

Progressive disclosure — A design pattern that shows only essential information initially, revealing details on demand.

Remediation — Fixing accessibility problems in existing designs. Costlier than building accessibly from the start.

Responsive design — Web design that adapts to different screen sizes and devices.

Ron Mace — Architect who coined “universal design” and founded the Centre for Universal Design. See history of universal design.

S-U

Screen reader — Assistive technology that reads digital content aloud. Examples: JAWS, NVDA, VoiceOver, TalkBack.

Section 508 — U.S. law requiring accessible federal information technology.

Sensory design — Design that engages multiple senses. See sensory design principles.

Sign language — A visual-gestural language used by deaf communities. There are over 300 distinct sign languages worldwide.

Social model — The understanding that disability is caused by social and environmental barriers, not individual impairments.

Switch access — An input method using one or more switches operated by any controllable body movement.

Tactile ground surface indicator (TGSI) — Textured paving that communicates information through touch.

Tolerance for error — Fifth principle of universal design. See tolerance for error.

Touch target — The interactive area of a UI element. WCAG 2.2 requires minimum 24x24 CSS pixels.

UDL — Universal Design for Learning. Educational framework by CAST.

Universal design — Design usable by all people to the greatest extent possible without adaptation.

Usability — The ease with which users can accomplish their goals with a product.

V-Z

VPAT — Voluntary Product Accessibility Template. Standardized document declaring product accessibility.

Wayfinding — Systems that help people navigate physical spaces. Includes signage, maps, landmarks, and digital navigation.

WCAG — Web Content Accessibility Guidelines. Published by W3C WAI. Current version: 2.2.

W3C WAI — World Wide Web Consortium Web Accessibility Initiative. Develops WCAG and other web accessibility resources.

Zero-step entrance — A building entrance at ground level requiring no steps or ramps.

For deeper exploration of any term, follow the internal links or browse our Foundations and Resources articles.

Key Takeaways

• Universal design draws terminology from architecture, technology, disability rights, education, and human factors — this glossary covers the most essential terms across all these domains.
• Understanding the vocabulary enables effective communication with stakeholders, compliance auditors, and the disability community.
• Many terms have specific technical meanings that differ from casual usage; precision matters in professional practice.

Sources

• W3C WAI — Glossary of Web Accessibility Terms: https://www.w3.org/WAI/fundamentals/
• W3C — WCAG 2.2 Glossary: https://www.w3.org/TR/WCAG22/#glossary
• Centre for Excellence in Universal Design — Terminology: https://universaldesign.ie/what-is-universal-design
• ADA.gov — ADA Definitions: https://www.ada.gov/law-and-regs/ada/