ADA Accessibility Glossary: Key Terms for Inclusive Design Compliance

Ian C. Langtree - Writer/Editor for Disabled World (DW)
Published: 2013/06/05 - Updated: 2025/04/23
Publication Type: Glossaries, Definitions
Topic: Glossary and Definitions - Publications List

Page Content: Synopsis - Introduction - Main - Insights, Updates

Synopsis: This information provides a comprehensive glossary of terms and guidelines related to the Americans with Disabilities Act (ADA), offering clear definitions for concepts such as "accessible route," "adaptability," and "area of rescue assistance." It serves as a practical reference for understanding the language and requirements associated with ADA compliance, which is essential for architects, designers, facility managers, and policymakers. By elucidating these terms, the resource aids in the creation of environments that are inclusive and navigable for individuals with disabilities, seniors, and others who benefit from accessible design. The glossary's authoritative nature stems from its alignment with ADA standards and its utility in promoting informed decision-making in accessibility planning - Disabled World (DW).

Introduction

Accessibility refers to the design of products, devices, services, vehicles, or environments to be usable by people with disabilities. Accessibility can be viewed as the "ability to access" and benefit from some system or entity. The concept focuses on enabling access for people with disabilities or enabling access through assistive technology; however, research and development in accessibility benefits everyone.

Focus

Glossary of Americans with Disabilities Act Terms

In this Glossary of ADA, the terms listed below are commonly used in accessibility and their definitions relating to technology, disability, and law.

Access Aisle

An accessible pedestrian space between elements, such as parking spaces, seating, and desks, that provides clearances appropriate for the use of the elements.

Accessible

Describes a site, building, facility, or portion thereof that complies with these guidelines.

Accessible Element

An element specified by the ADA guidelines (for example, telephone, controls, and the like).

Accessible Route

A continuous unobstructed path connecting all accessible elements and spaces of a building or facility. Interior accessible routes may include corridors, floors, ramps, elevators, lifts, and clear floor space at fixtures. Exterior accessible routes may include parking access aisles, curb ramps, crosswalks at vehicular ways, walks, ramps, and lifts.

Accessible Space

Space that complies with ADA guidelines.

Adaptability

The ability of certain building spaces and elements, such as kitchen counters, sinks, and grab bars, to be added or altered to accommodate the needs of individuals with or without disabilities or to accommodate the needs of persons with different types or degrees of disability.

Addition

An expansion, extension, or increase in the gross floor area of a building or facility.

Administrative Authority

A governmental agency that adopts or enforces regulations and guidelines for the design, construction, or alteration of buildings and facilities.

Alteration

An alteration is a change to a building or facility that affects or could affect the usability of the building or facility or part thereof. Alterations include, but are not limited to, remodeling, renovation, rehabilitation, reconstruction, historic restoration, resurfacing of circulation paths or vehicular ways, changes or rearrangement of the structural parts or elements, and changes or rearrangement in the plan configuration of walls and full-height partitions. Normal maintenance, re-roofing, painting or wallpapering, or changes to mechanical and electrical systems are not alterations unless they affect the usability of the building or facility.

Amusement Attraction

Any facility, or portion of a facility, located within an amusement park or theme park which amuses without the use of an amusement device. Examples include, but are not limited to, fun houses, barrels, and other attractions without seats.

Amusement Ride

A system that moves persons through a fixed course within a defined area for amusement.

Amusement Ride Seat

A seat that is built-in or mechanically fastened to an amusement ride intended to be occupied by one or more passengers.

Area of Rescue Assistance

An area, which has direct access to an exit, where people who are unable to use stairs may remain temporarily in safety to await further instructions or assistance during an emergency evacuation.

Area of Sport Activity

That portion of a room or space where the play or practice of a sport occurs.

Assembly Area

A room or space accommodating a group of individuals for recreational, educational, political, social, civic, or amusement purposes, or for the consumption of food and drink.

Automatic Door

A door equipped with a power-operated mechanism and controls that open and close the door automatically upon receipt of a momentary actuating signal. The switch that begins the automatic cycle may be a photoelectric device, floor mat, or manual switch (see power-assisted door).

Boarding Pier

A portion of a pier where a boat is temporarily secured to embark or disembark.

Boat Launch Ramp

A sloped surface designed for launching and retrieving trailered boats and other watercraft to and from a body of water.

Boat Slip

That portion of a pier, main pier, finger pier, or float where a boat is moored for berthing, embarking, or disembarking.

Building

Any structure used and intended for supporting or sheltering any use or occupancy.

Catch Pool

A pool or designated section of a pool used as a terminus for water slide flumes.

Circulation Path

An exterior or interior way of passage from one place to another for pedestrians, including, but not limited to, walks, hallways, courtyards, stairways, and stair landings.

Clear

Unobstructed.

Clear Floor Space

The minimum unobstructed floor or ground space required to accommodate a single, stationary wheelchair and occupant.

Closed Circuit Telephone

A telephone with dedicated lines(s) such as a house phone, courtesy phone or phone that must be used to gain entrance to a facility.

Common Use

Refers to those interior and exterior rooms, spaces, or elements that are made available for the use of a restricted group of people (for example, occupants of a homeless shelter, the occupants of an office building, or the guests of such occupants).

Cross Slope

The slope that is perpendicular to the direction of travel (see running slope).

Curb Ramp

A short ramp cutting through a curb or building up to it.

Detectable Warning

A standardized surface feature built in or applied to walking surfaces or other elements to warn visually impaired people of hazards on a circulation path.

Dwelling Unit

A single unit that provides a kitchen or food preparation area, in addition to rooms and spaces for living, bathing, sleeping, and the like. Dwelling units include a single-family home or a townhouse used as a temporary group home; an apartment building used as a shelter; guest rooms in a hotel that provide sleeping accommodations and food preparation areas; and other similar facilities used temporarily. For these guidelines, "Dwelling Unit" does not imply the unit is used as a residence.

Egress, Means of

A continuous and unobstructed way of exit travel from any point in a building or facility to a public way. A means of egress comprises vertical and horizontal travel and may include intervening room spaces, doorways, hallways, corridors, passageways, balconies, ramps, stairs, enclosures, lobbies, horizontal exits, courts, and yards. An accessible means of egress complies with these guidelines and does not include stairs, steps, or escalators. Areas of rescue assistance or evacuation elevators may be included as accessible means of egress.

Element

An architectural or mechanical component of a building, facility, space, or site, e.g., telephone, curb ramp, door, drinking fountain, seating, or water closet.

Elevated Play Component

A play component that is approached above or below grade and that is part of a composite play structure consisting of two or more play components attached or functionally linked to create an integrated unit providing more than one play activity.

Entrance

Any access point to a building or portion of a building or facility used to enter. An entrance includes the approach walk, the vertical access leading to the entrance platform, the entrance platform itself, vestibules, if provided, the entry door(s) or gate(s), and the hardware of the entry door(s) or gate(s).

Facility

All or any portion of buildings, structures, site improvements, complexes, equipment, roads, walks, passageways, parking lots, or other real or personal property located on a site.

Gangway

A variable-sloped pedestrian walkway that links a fixed structure or land with a floating structure. Gangways which connect to vessels are omitted.

Golf Car Passage

A continuous passage on which a motorized golf car can operate.

Ground Floor

Any occupiable floor less than one story above or below grade with direct access to grade. A building or facility always has at least one ground floor and may have more than one ground floor where a split-level entrance is provided, or a building is built into a hillside.

Ground Level Play Component

A play component that is approached and exited at the ground level.

Mezzanine or Mezzanine Floor

That portion of a story which is an intermediate floor level placed within the story and having occupiable space above and below its floor.

Marked Crossing

A crosswalk or other identified path intended for pedestrian use in crossing a vehicular way.

Multifamily Dwelling

Any building containing more than two dwelling units.

Occupiable

A room or enclosed space designed for human occupancy in which individuals congregate for amusement, educational, or similar purposes or in which occupants are engaged at labor, and which is equipped with means of egress, light, and ventilation.

Operable Part

A part of a piece of equipment or appliance used to insert or withdraw objects or to activate, deactivate, or adjust the equipment or appliance (for example, coin slot, pushbutton, handle).

Play Area

A portion of a site containing play components designed and constructed for children.

Play Component

An element intended to generate specific opportunities for play, socialization, or learning. Play components may be manufactured, natural, stand-alone, or part of a composite play structure.

Power-assisted Door

A door used for human passage with a mechanism that helps to open the door or relieves the opening resistance of a door upon the activation of a switch or a constant force applied to the door itself.

Private Facility

A place of public accommodation or a commercial facility subject to title III of the ADA and 28 C.F.R. part 36 or a transportation facility subject to title III of the ADA and 49 C.F.R. 37.45.

Public Facility

A facility or portion of a facility constructed by, on behalf of, or for the use of a public entity subject to title II of the ADA and 28 C.F.R. part 35 or title II of the ADA and 49 C.F.R. 37.41 or 37.43.

Public Use

Describes interior or exterior rooms or spaces that are made available to the general public. Public use may be provided at a building or facility that is privately or publicly owned.

Ramp

A walking surface that has a running slope greater than 1:20.

Running Slope

The slope that is parallel to the direction of travel (see cross slope).

Service Entrance

An entrance intended primarily for the delivery of goods or services.

Signage

Displayed verbal, symbolic, tactile, and pictorial information.

Site

A parcel of land bounded by a property line or a designated portion of a public right-of-way.

Site Improvement

Landscaping, paving for pedestrian and vehicular ways, outdoor lighting, recreational facilities, and the like, added to a site.

Sleeping Accommodations

Rooms in which people sleep; for example, dormitory and hotel or motel guest rooms or suites.

Soft Contained Play Structure

A play structure made up of one or more components where the user enters a fully enclosed play environment that utilizes pliable materials (e.g., plastic, netting, fabric).

Space

A definable area, e.g., room, toilet room, hall, assembly area, entrance, storage room, nook, courtyard, or lobby.

Story

That portion of a building is included between the upper surface of a floor and the upper surface of the floor or roof next above. If such a portion of a building does not include occupiable space, it is not considered a story for these guidelines. There may be more than one-floor level within a story, as in the case of a mezzanine or mezzanines.

Structural Frame

The structural frame shall be considered to be the columns and the rafters, beams, trusses, and spandrels having direct connections to the columns and all other members which are essential to the stability of the building as a whole.

TDD (Telecommunication Devices for the Deaf)

See text telephone.

TTY (Tele-Typewriter)

TTY (Teletypewriter) is a device that allows users to send typed messages across phone lines. Many people who are Deaf, deafened, hard of hearing, or who are deafblind may use TTYs to call other individuals.

Tactile

Describes an object that can be perceived using the sense of touch.

Technically Infeasible

In alteration work, if compliance with 4.1.6 is technically infeasible, the alteration shall provide accessibility to the maximum extent feasible. Any elements or features of the building or facility that are being altered and can be made accessible shall be made accessible within the scope of the alteration. Technically Infeasible means, concerning an alteration of a building or a facility, that it has little likelihood of being accomplished because existing structural conditions would require removing or altering a load-bearing member which is an essential part of the structural frame; or because other existing physical or site constraints prohibit modification or addition of elements, spaces, or features which are in full and strict compliance with the minimum requirements for new construction and which are necessary to provide accessibility.

Teeing Ground

In golf, the starting place for the hole to be played.

Text Telephone (TTY)

Machinery or equipment that employs interactive text-based communications through the transmission of coded signals across the standard telephone network. Text telephones can include, for example, TDDs (telecommunication display devices or telecommunication devices for deaf persons) or computers with special modems. Text telephones are also called TTYs, an abbreviation for teletypewriter.

Transfer Device

Equipment designed to facilitate the transfer of a person from a wheelchair or other mobility device to and from an amusement ride seat.

Transient Lodging

A building, facility, or portion thereof, excluding inpatient medical care facilities and residential facilities, that contains sleeping accommodations. Transient lodging may include but is not limited to, resorts, group homes, hotels, motels, and dormitories.

Transition Plate

A sloping pedestrian walking surface located at the end(s) of a gangway.

Use Zone

The ground level area beneath and immediately adjacent to a play structure or equipment that is designated by ASTM F 1487 Standard Consumer Safety Performance Specification for Playground Equipment for Public Use for unrestricted circulation around the equipment and on whose surface it is predicted that a user would land when falling from or exiting the equipment.

Vehicular Way

A route intended for vehicular traffic, such as a street, driveway, or parking lot.

Walk

An exterior pathway with a prepared surface intended for pedestrian use, including general pedestrian areas such as plazas and courts.

Insights, Analysis, and Developments

Author Credentials: Ian is an Australian-born writer, editor, and advocate who currently resides in Montreal, Canada. He is the founder and Editor-in-Chief of Disabled World, a leading resource for news and information on disability issues. With a global perspective shaped by years of travel and lived experience, Ian is a committed proponent of the Social Model of Disability-a transformative framework developed by disabled activists in the 1970s that emphasizes dismantling societal barriers rather than focusing solely on individual impairments. His work reflects a deep commitment to disability rights, accessibility, and social inclusion. To learn more about Ian's background, expertise, and accomplishments, visit his full biography.