ACE.D triptych

Definitions Related to Disability

Download PDF version

The following definitions and the overlap between the definitions illustrate the complexity of disorders considered disability. It is clear from this list that terms and their usage also change over time and that single definitions often fail to cover all aspects of disabilities even when referring to single types of disability. 

Americans with Disabilities Act (ADA): First comprehensive civil rights law passed in 1990 to address the needs of people with disabilities, prohibiting discrimination in employment, public services, public accommodations, and telecommunications. (Americans with Disabilities Act, 1990).

Americans with Disabilities Act Amendments Act (ADAAA): Modifications made in 2008 in response to the narrow interpretation of the ADA’s definition of disability by the U.S. Supreme Court which denied legal protection to many individuals with disability. (Americans with Disabilities Act Amendments Act, 2008).

Autism/Autism Spectrum Disorder: A developmental disability caused by differences in the brain resulting in significant social, communication and behavioral differences in how people interact with others, communicate, learn, and behave. It is considered a “developmental disorder” because symptoms generally appear in the first two years of life, although it can be diagnosed at any age. It is referred to as a “spectrum” disorder because of the wide variation in type and severity of symptoms and is not always accompanied by intellectual disability. (See “neuroatypical”, “neurodiverse”, and “neurotypical” below.) (National Institute of Mental Health, 2022).

Disability: A physical or mental impairment that substantially limits one or more major life activities; a record or history of such an impairment; or is regarded or perceived by others as having such an impairment. (Americans with Disabilities Act, 1990).

Disability: Disability is an umbrella term for impairments, activity limitations or participation restrictions. Further, disability is the dynamic interaction between health conditions such as diseases, disorders, or injuries and contextual factors, such as personal and environmental factors, that affect health. The definition incorporates both the medical and social models of disability to address the biological, individual and social perspectives that affect function and participation of an individual in daily and community life. Disability is part of being human and results from the interaction between health conditions (disabling conditions) and the environment. (World Health Organization, 2001).

Disability: A physical, mental, sensory, or social impairment that, in interaction with various barriers may hinder the full and effective participation of individuals in society on an equal basis with others. (United Nations Convention on The Rights of Persons With Disabilities, 2006).

Disabling condition: The underlying disorder or health condition that causes disability. Examples include stroke, heart disease, spinal cord injury, Alzheimer’s disease, Down syndrome, low vision, and cerebral palsy. Conditions that cause disability are not the same as disability and knowing about disabling conditions is not equivalent to understanding life with a disability. Knowledge about disabling conditions is essential but not sufficient for health care professionals to be able to provide quality health care to those with disability. (Smeltzer, 2021).

Disability, cognitive: A disability characterized by difficulty remembering, learning new things, concentrating, or making decisions that affect one’s everyday life. Cognitive disability ranges from mild to severe; it can occur across the life span and can be present at birth or acquired over one’s life span and with aging, as seen in Alzheimer’s dementia. Cognitive disabilities can include intellectual disability, autism spectrum disorders, brain injury, and dementias. The use of the terms cognitive disability and intellectual disability are determined in part by age at onset. Not all intellectual disabilities are considered cognitive disabilities. (Centers for Disease Control and Prevention, 2011).

Disability, developmental: A condition due to impairment in physical function, learning, language, or behaviors. It typically begins or becomes apparent during the developmental period (before age 18), may affect day-to-day functioning, and usually lasts throughout a person’s lifetime. Some developmental disabilities affect physical function or intellectual function only; others involve both physical and intellectual disabilities due to genetic or other causes, such as Down syndrome and fetal alcohol syndrome. (American Psychiatric Association, 2022; Centers for Disease Control and Prevention, n.d.). 

Disability, intellectual: A group of disorders characterized by a limited mental capacity and difficulty with adaptive behaviors such as managing money, schedules and routines, or social interactions. Intellectual disability originates before the age of 18 and may result from physical causes, such as autism or cerebral palsy, or from nonphysical causes, such as lack of stimulation and adult responsiveness. Limitations in adaptive behavior (self-help, mobility, health care, communication, domestic skills, consumer skills, community use, practical academic skills, and vocational skills) are used for the diagnosis or classification of intellectual disability. The severity of intellectual disability ranges from mild to profound. (American Psychiatric Association, 2022).

Disability, neurodevelopmental: Developmental disabilities of neurological origin that appear early in life are referred to as neurodevelopmental disorders. Examples are intellectual disabilities, communication disorders, autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), specific learning disorders (SLD), and movement disorders. This term is not used widely, but its use is increasing. (American Psychiatric Association, 2022).

Disability, physical or motor: A disability that affects motor function and the ability to use the arms or legs to carry out usual activities of daily living (walking, climbing stairs, caring for self). Physical disability may affect one’s ability in bathing, toileting, cooking, walking, transferring, or dressing. (Independence Care System, 2016).

Disability, psychiatric/mental health: A disability characterized by a wide range of behavioral and/or psychological problems, such as anxiety, mood swings, depression, and/or a compromised assessment of reality. Such disorders involve significant disturbances in thinking, emotional regulation or behavior. These disorders persist over time; are not in response to a particular event; and affect one’s ability to function in everyday work, family, or school life. (World Health Organization, 2022).

Disability, sensory: A disability that affects one or more of the five senses (hearing, vision, touch, taste, or smell); the term sensory disability is used most commonly to refer to loss of vision or hearing (e.g., blindness, visual impairment, deafness, or hearing impairment). (Centers for Disease Control & Prevention, 2023; World Health Organization, 2024).

Handicap: A physical or attitudinal constraint that is imposed upon a person, regardless of whether that person has a disability. A set of stairs would be a handicap for a wheelchair user. This term is no longer used to refer to a person with a physical or mental limitation; it more accurately describes inadequate accommodations that will enable a person to function without limitation. (ADA National Network, 2018).

Impairment: Problems in body function or structure such as a significant deviation or loss. May be loss of psychological, physiological, or anatomical structure or function. (World Health Organization, 2001).

Limitations, activity: Difficulties an individual may have in executing activities of daily living. (World Health Organization, 2001).

Mental retardation: An offensive term previously used to describe an intellectual disability. Term is no longer considered acceptable. (ADA National Network, 2018).

Neuroatypical and neurodiverse: Newer terms used to describe people of atypical developmental, intellectual and cognitive abilities. These terms are used to refer to people with autism or another developmental difference. Attention deficit/hyperactivity disorder (ADHD), autism, dyspraxia, and dyslexia all fall within the spectrum of neurodiverse conditions. “Neurodiversity” and are all neurodiverse conditions. Neurotypical refers to having typical developmental, intellectual, and cognitive abilities. (American Psychological Association, 2023).

Person-first language: Use of humanistic wording that refers to a person before referring to his/her condition or disorder: “the person with a disability” (person-first language) rather than “the disabled person” or “the disabled” (not person-first language). Some individuals prefer “identify-first” language, in which their disability is used to refer to them (autistic person) because they see their disability as central and important to their identity. The preferences for wording are changing, so it is always important to ask the person what language is preferred. (National Institutes of Health, 2023).

Reasonable accommodations: Any modification or adjustment to a job, work or educational setting that will enable a qualified applicant, employee or student with a disability to participate in the application process or perform essential job or educational functions; includes adjustments to assure that a qualified individual with a disability has rights and privileges in employment equal to those of employees without disabilities. (ADA National Network, 2018; U.S. Department of Health & Human Services).

Secondary conditions: The occurrence of conditions (medical, social, emotional, family, or community problems) related to having a primary disability; many secondary conditions are preventable or treatable; the prevalence of many secondary conditions increases with aging. (Institute of Medicine, 2007; Centers for Disease Control & Prevention, 2020).

Special Needs: A term used to indicate that someone, often a child, has a disability. Its use has come under increasing scrutiny in recent years, in part because it avoids the more correct term “disability”. Although the term is still used in educational systems (e.g. “special education”) and may be preferred by some parents, the term has no legal meaning. The term further suggests that someone with a disability has needs that differ from those of persons without disability; yet the needs are human needs shared by everyone else. (National Center on Disability and Journalism, 2021).

Universal design: Development/design of products, environment, systems, and services (e.g., health care) that are usable and welcoming to diverse groups, including persons with disability. Based on principles of simplicity, flexibility, and efficiency. (Office of Disability Employment Policy, n.d.).


ADA National Network (2018). Guidelines for Writing About People With Disabilities.

ADA National Network. (2020). Health Care and the Americans With Disabilities Act.

Americans with Disabilities Act (1990). 42 U.S.C. § 12101 et seq. (1990).

Americans with Disabilities Act Amendments Act (2008). Public Law 110–325, sec. 8, 122 Stat. 3553-3559 (2008).

American Psychiatric Association. (2022). Diagnostic and Statistical Manual of Mental Disorders, 5th Edition: DSM—TR.

American Psychological Association. (2023). Dictionary of Psychology.

Centers for Disease Control and Prevention. (n.d.). Developmental Disability Basics.

Centers for Disease Control and Prevention. (2011). Cognitive Impairment: A Call for Action, Now.

Centers for Disease Control and Prevention. (2020). Disability and Health Related Conditions.

Centers for Disease Control and Prevention. (2023). Fast Facts About Vision Loss.

Independence Care System, (2016). A blueprint for improving access to primary care for adults with physical disabilities.

Institute of Medicine. Committee on Disability in America. (2007). Secondary Conditions and Aging with Disability. MJ, Jette AM, editors. National Academies Press (US); Washington, DC.

National Center on Disability and Journalism. (2021). Disability Language Style Guide.

National Institutes of Health. Science, Health and Public Trust. (2023). Writing Respectfully: Person-First and Identity-First Language.

National Institute of Mental Health. (2022). Autism Spectrum Disorder. 

Office of Disability Employment Policy (n.d.).

Smeltzer, S. C. (2021). Delivering Quality Healthcare for People with Disability. Sigma Theta Tau, Inc., Indianapolis, IN.

United Nations. (2006). Convention on the Rights of Persons with Disabilities – CRPD.

U.S. Department of Justice. (2002). The Department of Justice Reasonable Accommodation Guidelines. Washington, DC: Au. 

World Health Organization. (2001). International Classification of Functioning, Disability and Health. Geneva, Switzerland: World Health Organization.

World Health Organization. (2022). Mental Disorders.

World Health Organization. (2024). Deafness and Hearing Loss.

Author Information

Suzanne C. Smeltzer, EdD, RN, ANEF, FAAN
Professor Emerita and Research Professor

Colleen Meakim, MSN, RN, CHSE-A, ANEF
Director, Second Degree Track

Bette Mariani, PhD, RN, ANEF, FAAN
Vice Dean for Academic Affairs and Professor

Kathryn M. Reynolds, MSN, RN, PNP
Clinical Assistant Professor 

M. Louise Fitzpatrick College of Nursing, Villanova University

© Suzanne C. Smeltzer, EdD, RN, ANEF, FAAN; Colleen Meakim, MSN, RN, CHSE-A, ANEF; Bette Mariani, PhD, RN, ANEF, FAAN; Kathryn M. Reynolds, MSN, RN, PNP; M. Louise Fitzpatrick College of Nursing, Villanova University, 2017. Revised May 23, 2024.

Users are asked to cite the source for these Villanova University developed resources as developed by the Villanova University College of Nursing and retrieved on the NLN website.