Autism Glossary: Key Terms & Definitions

A broad category of communication methods used by individuals who cannot rely on speech alone. AAC includes low-tech options (picture boards, PECS cards) and high-tech options (speech-generating devices, tablet apps like Proloquo2Go and TouchChat). AAC does not replace speech — research consistently shows it supports speech development. Any autistic individual who has difficulty with verbal communication should have their AAC needs assessed by a speech-language pathologist.

A therapeutic approach based on learning theory that uses systematic reinforcement to teach skills and reduce behaviors that interfere with learning or safety. ABA is the most researched behavioral intervention for autism and is covered by most insurance plans in New York under mental health parity law. The field has evolved significantly — modern ABA emphasizes naturalistic, child-led, and functional approaches rather than the rigid, repetitive drill formats of earlier decades. Parents should look for providers using naturalistic developmental behavioral interventions (NDBIs) and ask about their philosophical approach.

A federal civil rights law prohibiting discrimination against individuals with disabilities in employment, public accommodations, transportation, and government services. The ADA applies to autistic individuals and requires "reasonable accommodations" in workplaces and public settings. In schools, the ADA and Section 504 of the Rehabilitation Act provide additional protections beyond IDEA for students whose needs don't meet IDEA's educational eligibility criteria.

A neurodevelopmental condition characterized by inattention, impulsivity, and/or hyperactivity. ADHD co-occurs with autism in approximately 50–70% of cases. Both conditions affect executive function, sensory processing, and social interaction — and they require different and sometimes complementary interventions. An accurate dual diagnosis is important for appropriate treatment planning.

The current diagnostic term used in the DSM-5 (2013) for autism. ASD replaced earlier separate diagnoses including Autistic Disorder, Asperger's Syndrome, and PDD-NOS under a single spectrum model. ASD is diagnosed based on persistent differences in social communication and interaction, plus restricted/repetitive behaviors, present from early development. The spectrum reflects enormous diversity — no two autistic individuals are alike. "Autism" and "ASD" are often used interchangeably.

A former diagnostic category (DSM-IV) describing autistic individuals with average to above-average intelligence and no significant language delay. Removed from the DSM-5 in 2013, absorbed into the broader ASD diagnosis. Many individuals who received an Asperger's diagnosis still identify with that label. In clinical settings, these individuals would now receive an ASD Level 1 diagnosis. Note: Hans Asperger's collaboration with Nazi policies has made the use of his name controversial in some advocacy communities.

The practical skills needed to function independently in daily life — including self-care (dressing, hygiene, eating), home living, community navigation, social skills, and functional academics. Adaptive behavior is formally assessed using tools like the Vineland Adaptive Behavior Scales and is considered in both autism diagnosis and disability eligibility determinations. Gaps between cognitive ability and adaptive functioning are common in autism and inform support planning.

A licensed professional trained in applied behavior analysis who designs, supervises, and evaluates behavior intervention programs. BCBAs hold a master's or doctoral degree and pass a national certification exam. In New York, BCBAs who provide ABA services must also be licensed as Licensed Behavior Analysts (LBAs). When seeking ABA services, verify both BCBA certification and NYS LBA licensure.

A written plan developed as part of the IEP process for students whose behavior impedes their own learning or the learning of others. A BIP must be based on a Functional Behavior Assessment (FBA) and includes strategies to address the function of the behavior, not just its surface appearance. In NYS, if a student has three suspensions in a school year or any suspension for a disability-related behavior, a BIP must be in place.

A state of chronic exhaustion, reduced functioning, and increased autistic traits resulting from sustained masking, prolonged stress, and sensory/social demands exceeding an individual's capacity. Autistic burnout is distinct from general burnout and can last months or years. It is increasingly recognized in clinical literature as a major factor in mental health crises among autistic adults, particularly those who were not diagnosed or supported in childhood. Prevention requires reducing masking demands and building genuine accommodations.

Medical, psychiatric, or developmental conditions that occur alongside autism. Extremely common — most autistic individuals have at least one co-occurring condition. Common co-occurring conditions include ADHD, anxiety disorders, depression, OCD, epilepsy, GI issues, sleep disorders, sensory processing disorder, intellectual disability, and learning disabilities. Co-occurring conditions require separate diagnosis and treatment; they are not just "part of autism."

In New York State, the CSE is the multidisciplinary team responsible for determining eligibility for and developing IEPs for school-age children (5–21). The CPSE does the same for preschool children ages 3–5. Both committees include the parent, the child's teacher(s), a school psychologist, and other relevant specialists. Parents are required members of both committees. Meeting notices, evaluation consents, and IEP documents must be provided in the parent's language.

The American Psychiatric Association's diagnostic manual used by clinicians in the United States. The DSM-5 (2013) established the current ASD diagnostic criteria and introduced the severity level system (Level 1, 2, 3). DSM-5-TR (Text Revision, 2022) maintained the same ASD criteria with minor clarifications. Note: The ICD-11 (used internationally) also has an autism diagnosis that aligns closely but not identically with DSM-5 criteria.

A structured ABA teaching method that breaks skills into small, discrete components and teaches them through repeated practice trials with reinforcement. DTT is one of many ABA techniques and is particularly useful for early skill acquisition. Modern practice integrates DTT with naturalistic and play-based approaches rather than using it as the sole instructional format.

When an individual has two or more distinct diagnoses — for example, autism plus intellectual disability, or autism plus bipolar disorder. In autism contexts, "dual diagnosis" often specifically refers to the co-occurrence of autism and intellectual disability (ID), affecting roughly 30% of autistic individuals. Each diagnosis requires its own assessment and support plan.

A federally mandated program (Part C of IDEA) providing developmental services to children from birth to age 3 with disabilities or developmental delays. In New York State, EI is administered by the NYS Department of Health and delivered through county health departments. EI services are provided at no cost to families and include speech therapy, occupational therapy, physical therapy, special instruction, and family support. A child must be referred and evaluated before turning 3 to access EI services.

Special education services provided beyond the regular school year for students whose IEPs require it. ESY is not optional summer school — it is an individually determined right under IDEA for students who would experience significant regression during a school break that would take an inordinate amount of time to recoup. In NYS, the CSE must consider ESY at every IEP development meeting. ESY eligibility is based on regression-recoupment data, not on severity of disability alone.

A set of cognitive skills managed by the prefrontal cortex including planning, working memory, cognitive flexibility, impulse control, task initiation, and organization. Executive function difficulties are common in autism (and ADHD) and affect academic performance, daily living, and social function. Strategies to support executive function include visual schedules, written task lists, timers, and environmental organization.

A core right under IDEA (Individuals with Disabilities Education Act). Every child with a disability is entitled to a free appropriate public education in the least restrictive environment. "Appropriate" does not mean the best possible education — it means an education reasonably calculated to enable the child to make meaningful progress in light of their circumstances (per Endrew F. v. Douglas County School Dist., 2017 Supreme Court ruling).

A process used to identify the function (purpose) of a challenging behavior — what the behavior is communicating or achieving for the individual. FBA findings must drive the development of a Behavior Intervention Plan (BIP). Common behavior functions include: access to tangible items or activities, escape/avoidance, attention, and sensory/automatic reinforcement. Understanding function is essential because two behaviors that look identical can serve completely different functions and require different interventions.

The transfer of a learned skill from the teaching context to other environments, people, and materials. Generalization is a significant challenge in autism — a child may demonstrate a skill in therapy or at school but not apply it at home or with different people. Effective intervention intentionally programs for generalization by teaching across multiple settings, people, and materials from the beginning of instruction.

Two ends of sensory reactivity. Hypersensitivity (over-responsivity) means a heightened response to sensory input — a touch that feels like pain, a sound that is overwhelmingly loud. Hyposensitivity (under-responsivity) means a reduced response to sensory input — needing intense sensory stimulation to register it at all, such as seeking very firm pressure, loud music, or strong flavors. Many autistic individuals experience both simultaneously across different senses or contexts.

An umbrella term covering conditions with onset before age 22 that significantly limit intellectual functioning and adaptive behavior. Autism is an IDD. This term is used in legal, policy, and service contexts, including OPWDD eligibility in New York State.

The federal law governing special education in public schools. IDEA ensures children with disabilities receive a Free Appropriate Public Education (FAPE) in the Least Restrictive Environment (LRE) through an Individualized Education Program (IEP). IDEA also mandates due process protections allowing parents to dispute school decisions. IDEA covers children from birth through age 21 in three parts: Part C (birth–2), Part B (3–21).

A legally binding document developed by a multidisciplinary team (including parents) that outlines a student's present levels of performance, annual goals, special education services, related services, accommodations, and placement. IEPs are required for students eligible for special education under IDEA and must be reviewed and updated at least annually. Parents have the right to participate in all IEP decisions and to dispute them through mediation or due process.

The practice of educating students with disabilities alongside their non-disabled peers in general education settings, with appropriate supports. True inclusion differs from mainstreaming or integration — it requires environmental and instructional modifications that enable genuine participation, not just physical presence. IDEA's LRE mandate supports inclusion, though the appropriate setting for each student is individually determined.

An IDEA requirement that students with disabilities be educated alongside non-disabled peers to the maximum extent appropriate. LRE does not mean all students must be fully included in general education — it means that removal from the general education environment occurs only when the nature or severity of the disability makes education in general education unsatisfactory even with supplementary aids and services. LRE exists on a continuum from full inclusion to specialized schools.

The practice of suppressing or hiding autistic traits to appear neurotypical in social situations. Masking may include forcing eye contact, learning and mimicking social scripts, suppressing stimming, and monitoring body language — all requiring significant cognitive and emotional effort. Research links chronic masking to increased anxiety, depression, and autistic burnout. Masking contributes to delayed diagnoses, particularly in girls, women, and people of color. Reducing masking demands through genuine accommodation improves wellbeing and long-term outcomes.

An intense response to overwhelm — sensory, emotional, or cognitive — that involves a temporary loss of behavioral control. Meltdowns are not tantrums (which are goal-directed behaviors seeking a specific outcome); they are neurological events triggered by overload. During a meltdown, an autistic person is not "choosing" to behave badly — they have exceeded their capacity to regulate. The correct response is to reduce stimulation, ensure safety, and avoid demands until the person has recovered.

A concept and social movement asserting that neurological differences — including autism, ADHD, dyslexia, and others — are natural variations in the human genome rather than disorders to be cured. The neurodiversity framework emphasizes accommodation and acceptance alongside appropriate support. Within autism advocacy, there is ongoing debate between neurodiversity perspectives (emphasizing acceptance and adaptation) and medical perspectives (emphasizing treatment and intervention). Many families and autistic individuals hold nuanced views that incorporate elements of both.

Preferred terms (over "nonverbal") for individuals who do not use or have limited use of spoken language as a communication method. Approximately 25–30% of autistic people are nonspeaking or minimally verbal. Being nonspeaking does not indicate low intelligence or inability to learn — many nonspeaking autistic individuals demonstrate complex understanding when given appropriate communication access (AAC). "Presume competence" is a core principle in supporting nonspeaking individuals.

New York State's primary agency funding and overseeing services for individuals with developmental disabilities, including autism. OPWDD funds residential services, day habilitation, community habilitation, employment supports, respite, family support, and more. OPWDD eligibility requires a developmental disability diagnosis (including autism) with onset before age 22 and significant functional limitations in at least three adaptive skill areas. Eligibility determination is through an OPWDD Developmental Disabilities Regional Office (DDRO).

A therapeutic discipline focusing on developing the skills needed for meaningful daily activities ("occupations") — including fine motor skills, sensory processing, self-care, handwriting, executive function, and play skills. OT is one of the most commonly provided related services for autistic students in schools. OTs also develop sensory diets and sensory accommodations for home and classroom environments. Occupational therapists may hold specialization in Sensory Integration (SI) or DIR/Floortime approaches.

An AAC system developed by Andy Bondy and Lori Frost that teaches communication by exchanging picture cards for desired items or activities. PECS is implemented in a structured phase system and has a robust evidence base for increasing communication in minimally verbal autistic children. As a lower-tech option, PECS can be implemented anywhere and provides a foundation for more complex communication systems.

The sensory system that tells the brain where the body is in space — the sense of body position, movement, and force. Many autistic individuals have differences in proprioceptive processing. Under-responsivity may manifest as seeking deep pressure, crashing into things, or using excessive force; over-responsivity may make physical activities uncomfortable. Proprioceptive input (heavy work, weighted items, compression clothing) is commonly used as a regulating strategy.

A former DSM-IV diagnostic category used for individuals who met some but not all criteria for Autistic Disorder. Removed from the DSM-5 in 2013 and subsumed under ASD. Individuals previously diagnosed with PDD-NOS retain their eligibility for services under a DSM-5 ASD diagnosis, and practitioners were instructed to continue recognizing prior diagnoses.

The loss of previously acquired skills. Regression in autism can occur during times of stress, illness, environmental change, or breaks from services. Approximately 30% of autistic children experience a period of developmental regression, most commonly between 18–24 months. Regression after school breaks (summer, extended illness) is one of the primary reasons Extended School Year (ESY) services are provided. Documentation of regression is important evidence for ESY eligibility.

Supportive services provided under IDEA that help a student benefit from special education — including speech-language therapy, occupational therapy, physical therapy, counseling, transportation, behavioral support, and more. Related services must be included in the IEP if the student needs them to access their education. In New York State, related services providers are licensed professionals and their services must be educationally relevant.

The right and ability of individuals to make choices and decisions about their own lives. Self-determination is a key goal in transition planning for autistic adolescents and young adults. Supported decision-making (rather than guardianship) is increasingly recognized as a preferred approach that honors autistic adults' rights while providing needed support — available in New York State under the Supported Decision-Making agreements framework.

An individualized plan, typically developed by an occupational therapist, of sensory activities and accommodations scheduled throughout the day to help an individual maintain optimal sensory regulation. Not a food diet — a "diet" of sensory input. May include movement breaks, weighted items, oral sensory activities, fidget tools, and environmental modifications. Effectiveness is highly individual and should be developed and monitored by a qualified OT.

A condition in which the brain has difficulty receiving and responding appropriately to sensory input. SPD is distinct from but highly overlapping with autism — many autistic individuals have SPD, but SPD can also occur independently. SPD is not currently a standalone DSM-5 diagnosis; sensory differences in autism are captured under the "restricted/repetitive behaviors" criterion. SPD is assessed and treated primarily through occupational therapy using a sensory integration framework.

An inward response to overload — the opposite of a meltdown in appearance but the same in cause. During a shutdown, an autistic person may become very still, quiet, and unresponsive. They may appear to "switch off." Shutdowns can be mistaken for compliance, boredom, or sulking. They require the same response as meltdowns: reduced demands, reduced stimulation, and patient support until the person has recovered.

A licensed clinician who evaluates and treats communication disorders, including speech, language, social communication, fluency, voice, and swallowing. SLPs are among the most important providers for autistic individuals across the lifespan — supporting speech development, AAC use, social pragmatic communication, feeding issues, and more. School-based SLPs focus on educationally relevant communication goals; outpatient SLPs may address a broader range of functional communication goals.

A legal trust structure designed to hold assets for a person with a disability without disqualifying them from means-tested public benefits (SSI, Medicaid). There are two primary types: first-party (d)(4)(A) trusts funded with the beneficiary's own assets, and third-party trusts funded by family members. SNTs are an essential component of long-term financial planning for autistic individuals. Families should consult a special needs estate planning attorney when setting up an SNT.

Repetitive movements, sounds, or sensory behaviors used by autistic individuals for self-regulation, sensory input, emotional expression, and coping. Common examples include hand-flapping, rocking, spinning, vocalizations, repeating words or phrases, and rubbing textures. Stimming serves important functions — it is not a behavior that needs to be eliminated unless it causes physical harm. Suppressing stimming increases stress and contributes to masking and burnout. The autism self-advocacy community strongly supports the right to stim.

An alternative to guardianship in which an individual with a disability makes their own decisions with the support of trusted people (supporters) who help them understand information and communicate choices. In New York State, Supported Decision-Making Agreements are available under the Supported Decision-Making Act (effective 2023), allowing adults with disabilities to formalize support arrangements without surrendering legal decision-making authority.

The IEP-based planning process for students with disabilities preparing for life after high school — including post-secondary education, vocational training, integrated employment, adult services, and community living. Under IDEA, transition planning must begin no later than age 16 in the IEP (New York State requires it to begin at age 15). Effective transition planning is individualized, strengths-based, and actively involves the student themselves.

An educational framework developed by CAST that guides the design of flexible learning environments accommodating individual learning differences. UDL provides multiple means of representation (how information is presented), action and expression (how students respond), and engagement (how students are motivated). UDL accommodations designed for students with disabilities benefit all learners and reduce the need for individual accommodations by making flexibility the default.

The sensory system in the inner ear that processes movement, balance, and spatial orientation. Vestibular differences are common in autism — some individuals seek intense movement (spinning, swinging) while others are hypersensitive and may find unexpected movement frightening. Vestibular input is one of the "heavy work" categories used in occupational therapy for sensory regulation.

The behavior of leaving a safe, supervised area without warning — a significant safety concern for approximately 49% of autistic children. Wandering may be goal-directed (approaching a desired location), escape-driven (fleeing an overwhelming environment), or sensory-seeking. Drowning is the leading cause of death from wandering in autistic children. See the full GRSCorp safety guide for prevention strategies, GPS tools, and emergency planning.