Autism Glossary: Definitions & Everyday Meaning

Definitions • Everyday meaning • AnalogiesSources checked September 17, 2026

These are plain-language summaries of the linked sources, not verbatim diagnostic criteria. Each entry identifies whether it is clinical, educational, descriptive, or a debated idea. Open the source for its full definition and context.

The analogies are original illustrations, not clinical explanations or statements about every autistic person. Use them to ask better questions, then listen to the individual. This reference covers commonly encountered terminology; it is not an exhaustive diagnostic manual.

Start with the child: Difficulty is information. Before deciding what a behavior means, consider communication, pain, sensory experiences, demands, and safety. A new or sudden change needs appropriate assessment.

Find the meaning

Words you may hear.

Search a term or abbreviation, or choose a topic. Each entry has its own link to share.

Safety and healthClinical meaning

Adaptive skills

Definition, in plain language: Conceptual, social, and practical skills used in daily life.
What this can mean: Support can differ across dressing, communication, money, and safety.
A way to picture it: Reading a map and navigating the journey are related but different abilities.

Source: AAIDD: intellectual disability and adaptive behavior

Safety and healthClinical term and community shorthand

ADHD and AuDHD

Definition, in plain language: ADHD involves persistent, impairing inattention and/or hyperactivity and impulsivity. AuDHD is informal shorthand for coexisting autism and ADHD.
What this can mean: A separate assessment identifies ADHD.
A way to picture it: Two overlapping sets of needs can require more than one kind of support.

Source: NIMH: ADHD

Safety and healthClinical meaning

Anxiety disorders

Definition, in plain language: Conditions involving persistent or excessive fear or anxiety that interferes with life.
What this can mean: Anxiety is not automatically explained by autism.
A way to picture it: An alarm can keep sounding long after others think the danger has passed.

Source: NIMH: anxiety disorders

Therapy and toolsClinical approach

Applied behavior analysis (ABA)

Definition, in plain language: An approach using learning and behavior principles, with measured progress toward selected goals.
What this can mean: Ask whose goals are being served and how comfort, communication, and choice are protected.
A way to picture it: Before measuring progress along a road, make sure it leads somewhere meaningful for the child.

Source: CDC: treatment and intervention

CommunicationClinical meaning

Augmentative and alternative communication (AAC)

Definition, in plain language: Communication methods that supplement or replace speech, including gestures, symbols, writing, and speech-generating technology.
What this can mean: The right system is matched to the person.
A way to picture it: A ramp creates another way in. AAC creates another way to be heard.

Source: ASHA: AAC practice guidance

DiagnosisClinical meaning

Autism spectrum disorder (ASD)

Definition, in plain language: A developmental condition involving differences in social communication, behavior, interests, and sensory experiences.
What this can mean: Abilities and support needs differ from person to person.
A way to picture it: A shared diagnosis is a map legend. You still need to learn the individual landscape.

Source: World Health Organization

RegulationResearch and lived-experience term

Autistic burnout

Definition, in plain language: Prolonged exhaustion, reduced functioning, and lower tolerance for stimulation associated with sustained stress and insufficient support.
What this can mean: This is more than a tiring afternoon; other causes also need assessment.
A way to picture it: Resting briefly cannot refill a reservoir that has been draining for months.

Source: National Autistic Society: research on autistic burnout

CommunicationClinical meaning

Childhood apraxia of speech (CAS)

Definition, in plain language: A motor speech disorder involving difficulty planning or programming the movements needed for speech.
What this can mean: A speech-language pathologist assesses it; it is not assumed from autism.
A way to picture it: Knowing the tune and coordinating the instrument are different tasks.

Source: ASHA: childhood apraxia of speech

RegulationClinical meaning

Cognitive flexibility

Definition, in plain language: The ability to adjust thinking or behavior as circumstances change.
What this can mean: Switching tasks may require support.
A way to picture it: Changing direction is easier when someone shows where the next road leads.

Source: Harvard Center on the Developing Child: executive function

RegulationDescriptive term • contested profile

Demand avoidance and PDA

Definition, in plain language: Marked resistance to everyday demands; PDA is a debated proposed profile, not a standalone DSM or ICD diagnosis.
What this can mean: Look at distress and context rather than assuming defiance.
A way to picture it: A request can feel like a closing door when the person needs room to move.

Source: National Autistic Society: demand avoidance and the PDA debate

DiagnosisDiagnostic frameworks

DSM and ICD

Definition, in plain language: Classification systems used by clinicians to describe and diagnose conditions; autism terminology differs between them.
What this can mean: Ask which framework your report uses.
A way to picture it: Two maps can label the same place differently. Read the key before comparing the labels.

Source: National Autistic Society: diagnostic frameworks

CommunicationClinical meaning

Echolalia

Definition, in plain language: Repetition of previously heard words or phrases, immediately or after a delay.
What this can mean: A familiar phrase may be connected to a need or experience.
A way to picture it: Sometimes a child borrows a sentence before they can build one for the moment.

Source: NIDCD: autism and communication

School and rightsU.S. civil rights • ADA

Effective communication

Definition, in plain language: Covered organizations must communicate effectively with people with communication disabilities using appropriate aids or services where required.
What this can mean: The method depends on the person and the situation.
A way to picture it: Information has not arrived just because it has been spoken. The connection must work both ways.

Source: U.S. Department of Justice: effective communication

School and rightsEngland • education law

EHC plan or EHCP

Definition, in plain language: An education, health and care plan for eligible children and young people needing more support than SEN support provides.
What this can mean: This is an England-specific framework, not a UK-wide IEP.
A way to picture it: Different countries use different maps for arranging a child’s support. Check the map for your location.

Source: GOV.UK: EHC plans in England

Safety and healthSafety terminology

Elopement or wandering

Definition, in plain language: Leaving a safe area or responsible supervision in a way that can expose the person to harm.
What this can mean: Reasons vary; the safety risk needs an individual plan.
A way to picture it: A child’s route and the adult’s safety map may not match.

Source: CDC: wandering and elopement

Safety and healthClinical meaning

Epilepsy

Definition, in plain language: A neurological condition involving a continuing tendency to have seizures.
What this can mean: A seizure is not a behavioral choice; medical assessment is essential.
A way to picture it: A disruption in electrical signaling needs medical understanding, not a lesson in cooperation.

Source: MedlinePlus: epilepsy

RegulationClinical meaning

Executive function

Definition, in plain language: Mental processes involved in planning, attention, remembering instructions, and managing tasks.
What this can mean: Knowing what to do and organizing how to do it can differ.
A way to picture it: Having every ingredient does not automatically put the recipe in order.

Source: Harvard Center on the Developing Child: executive function

CommunicationClinical meaning

Expressive language

Definition, in plain language: The use of language to convey ideas, needs, or information.
What this can mean: Language can be expressed through speech, signs, or other communication systems.
A way to picture it: The message can leave through more than one doorway. Speech is one of them.

Source: ASHA: spoken language

School and rightsU.S. education law • IDEA

FAPE

Definition, in plain language: Free appropriate public education: special education and related services meeting IDEA’s requirements, including provision under an IEP.
What this can mean: Appropriate education is individualized.
A way to picture it: A seat in the classroom is only the starting point; the child needs access to learning.

Source: U.S. Department of Education: FAPE definition

RegulationDescriptive meaning

Focused or special interests

Definition, in plain language: Subjects or activities that someone engages with especially deeply.
What this can mean: These interests can bring joy, connection, and learning.
A way to picture it: An interest can be a doorway into the child’s world. Meet them there.

Source: National Autistic Society: focused interests

CommunicationTheory • evidence limits

Gestalt language processing (GLP)

Definition, in plain language: A proposed account of learning language in larger chunks; its application to autistic language development remains debated.
What this can mean: Repeating phrases does not establish a separate diagnosis or prove a particular therapy is effective.
A way to picture it: One familiar route through language does not tell us every route a child can take.

Source: ASHA: autism practice guidance

DiagnosisLanguage preference

Identity-first and person-first language

Definition, in plain language: “Autistic person” puts identity first; “person with autism” puts the person first in the phrase.
What this can mean: Ask what the person prefers.
A way to picture it: The person gets a say in the words on their own name card.

Source: Harvard Health: neurodiversity and respectful language

School and rightsU.S. education law

IEP

Definition, in plain language: An Individualized Education Program: a written plan of special education, goals, and services for an eligible child under IDEA.
What this can mean: The plan connects assessed needs with specified educational support.
A way to picture it: It should be a working set of directions for the child’s school day, not just a folder on a shelf.

Source: U.S. Department of Education: IEP definition

Safety and healthClinical meaning

Intellectual disability

Definition, in plain language: Significant limitations in intellectual functioning and adaptive behavior originating during the developmental period.
What this can mean: It is assessed separately from autism and speech.
A way to picture it: One part of a learning profile cannot stand in for the whole picture.

Source: AAIDD: intellectual disability and adaptive behavior

SensoryClinical meaning

Interoception

Definition, in plain language: Sensing and interpreting signals from inside the body.
What this can mean: Hunger, thirst, or a full bladder may be difficult to identify.
A way to picture it: The body sends notifications. Some arrive quietly, late, or without a clear label.

Source: Schmitt & Schoen: interoception review, PubMed Central

School and rightsU.S. education law • IDEA

LRE

Definition, in plain language: Least restrictive environment: education with nondisabled peers to the maximum extent appropriate, with required consideration of supplementary aids and services.
What this can mean: Placement is an individual decision, not one setting for every child.
A way to picture it: Choosing a classroom means considering both belonging and the support needed to learn there.

Source: U.S. Department of Education: LRE requirements

RegulationDescriptive meaning

Masking

Definition, in plain language: Conscious or unconscious efforts to hide autistic characteristics or appear nonautistic.
What this can mean: Visible coping can conceal substantial effort.
A way to picture it: A carefully held smile does not show how heavy the day has been.

Source: National Autistic Society: masking

RegulationDescriptive meaning

Meltdown

Definition, in plain language: An intense response to overwhelm involving a temporary loss of behavioral control.
What this can mean: Consider what has exceeded the person’s capacity.
A way to picture it: When a cup is overflowing, asking it to hold more will not create room.

Source: National Autistic Society: meltdowns

School and rightsAustralia • support scheme

NDIS

Definition, in plain language: The National Disability Insurance Scheme funds eligible disability supports under Australian rules.
What this can mean: An autism diagnosis alone does not establish all eligibility or funding decisions.
A way to picture it: A diagnosis describes needs; the funding pathway has its own entry criteria and decisions.

Source: NDIA: NDIS eligibility

DiagnosisCommunity and social concept

Neurodiversity

Definition, in plain language: The variety of ways people think, learn, and experience the world.
What this can mean: Respecting differences includes recognizing disability and providing needed support.
A way to picture it: Different minds can take different routes through the same lesson. Access means making room for those routes.

Source: Harvard Health: neurodiversity and respectful language

CommunicationDescriptive language

Nonverbal and nonspeaking

Definition, in plain language: Terms commonly used for someone who does not use spoken words, or uses very few; usage varies.
What this can mean: Speech alone cannot establish someone’s understanding.
A way to picture it: When one route is unavailable, we need to explore other routes for communication and understanding.

Source: ASHA: autism practice guidance

Therapy and toolsClinical profession

Occupational therapy (OT)

Definition, in plain language: Therapy supporting participation in everyday activities and skills.
What this can mean: Goals can involve dressing, eating, and other daily routines.
A way to picture it: Support can change both the task and the tools so participation becomes possible.

Source: CDC: treatment and intervention

Safety and healthClinical meaning

Pica

Definition, in plain language: Eating nonfood substances for at least one month when developmentally inappropriate and not a culturally supported practice.
What this can mean: It can cause serious harm and needs medical assessment.
A way to picture it: An object can look harmless in a hand and become dangerous inside the body.

Source: MedlinePlus: pica

SensoryClinical meaning

Proprioception

Definition, in plain language: The sense of body position and movement, using information from muscles and joints.
What this can mean: It helps us know where our limbs are without looking.
A way to picture it: It is the body’s position map, updating as we move.

Source: Arnold and colleagues: interoception and proprioception

CommunicationClinical meaning

Receptive language

Definition, in plain language: The understanding of language.
What this can mean: What a child understands needs its own assessment.
A way to picture it: Receiving a message and sending a reply are different parts of the conversation.

Source: ASHA: spoken language

DiagnosisClinical distinction

Screening and diagnosis

Definition, in plain language: Screening identifies possible developmental concerns; a diagnostic evaluation examines whether diagnostic criteria are met.
What this can mean: A screening result is not a diagnosis.
A way to picture it: A smoke alarm tells you to investigate. It does not tell you everything that caused the signal.

Source: CDC: screening and diagnosis

School and rightsU.S. civil rights law

Section 504

Definition, in plain language: A federal disability nondiscrimination law covering recipients of federal financial assistance, including public schools.
What this can mean: School obligations and eligibility differ from IDEA.
A way to picture it: Removing a barrier makes the doorway usable, instead of asking the child to squeeze through it.

Source: U.S. Department of Education: Section 504

SensoryClinical meaning

Sensory hypersensitivity

Definition, in plain language: Heightened sensitivity to sensory input.
What this can mean: Ordinary sensations may feel intense.
A way to picture it: A small sound can arrive like a loudspeaker.

Source: National Autistic Society: sensory processing

SensoryClinical meaning

Sensory hyposensitivity

Definition, in plain language: Reduced sensitivity or responsiveness to sensory input.
What this can mean: Some signals may be harder to notice.
A way to picture it: A signal can arrive like a whisper across a room.

Source: National Autistic Society: sensory processing

SensoryDescriptive meaning

Sensory overload

Definition, in plain language: Sensory input that becomes overwhelming.
What this can mean: Reduce the load and allow recovery.
A way to picture it: Imagine several conversations playing through one speaker. More instructions add another voice.

Source: National Autistic Society: sensory processing

SensoryClinical meaning

Sensory processing

Definition, in plain language: How the nervous system interprets sensory information.
What this can mean: The same room can feel different to different people.
A way to picture it: We may share the room without sharing its volume.

Source: National Autistic Society: sensory processing

DiagnosisDescriptive language

Severe autism and high support needs

Definition, in plain language: Terms used to discuss substantial assistance needs; they do not by themselves provide a complete clinical profile.
What this can mean: Specify the person’s communication, care, and safety needs.
A way to picture it: A label on a suitcase cannot tell you everything the person must carry. Ask what would make the load manageable.

Source: Harvard Health: neurodiversity and respectful language

RegulationDescriptive meaning

Shutdown

Definition, in plain language: An inward response to overwhelm that may involve withdrawal and reduced ability to respond.
What this can mean: Quiet does not always mean comfortable.
A way to picture it: A room can go dark while everything inside still needs care.

Source: Ambitious about Autism: meltdowns and shutdowns

Therapy and toolsClinical profession

Speech and language therapy

Definition, in plain language: Assessment and support for speech, language, and communication needs.
What this can mean: Communication support may include alternatives to speech.
A way to picture it: The goal is a usable connection between people, with more than one way to make it.

Source: CDC: treatment and intervention

RegulationDescriptive meaning

Stimming

Definition, in plain language: Repeated movements, sounds, or actions that can provide sensory input, enjoyment, or regulation.
What this can mean: Harmless stimming can serve a purpose.
A way to picture it: A familiar rhythm can be a handrail through a busy moment.

Source: National Autistic Society: stimming

DiagnosisClinical meaning

Support levels: 1, 2, and 3

Definition, in plain language: DSM descriptions of requiring support, substantial support, or very substantial support, assessed across two diagnostic domains.
What this can mean: The level is one part of an assessment.
A way to picture it: Think of the support written beside a task, not a grade written beside a child.

Source: CDC: diagnostic criteria

RegulationEveryday support language

Transitions and predictability

Definition, in plain language: Transitions are changes between activities or situations; predictability means knowing what to expect.
What this can mean: Advance information can help some people manage change.
A way to picture it: Turning a page is easier when you know the story has not disappeared.

Source: National Autistic Society: predictability and routine

SensoryClinical meaning

Vestibular system

Definition, in plain language: The inner-ear system that helps detect head movement and position and contributes to balance.
What this can mean: It works with vision and body signals.
A way to picture it: It helps steady the horizon while the body moves.

Source: NIDCD: the balance system

Therapy and toolsSupport method

Visual supports

Definition, in plain language: Objects, pictures, symbols, or written cues that make information accessible and help explain tasks or routines.
What this can mean: A visual must make sense to its user.
A way to picture it: Spoken directions disappear. A useful visual leaves the directions where the child can return to them.

Source: ASHA: autism practice guidance

Keep the person bigger than the label.

Words can have different meanings across services and countries. Ask the author of an assessment to explain the terms and framework they used.

For school plans, advocacy, and local services, use the country-specific links in the resource hub. This glossary is educational information, not an individual diagnosis, treatment plan, or legal decision.

Find support where you live → · Suggest a term or report a correction