ADHD comes with its own vocabulary, and a lot of it gets thrown around without explanation. Some of the terms are clinical, some are coined by the community, and some are quietly misleading. This A to Z gathers the words, ideas and reminders worth knowing, whether you have just started looking into ADHD or have lived with the diagnosis for years. It is not a substitute for an assessment or for clinical advice, but it is a fair map of the territory, grouped into the things that tend to matter most.
A to D: assessment, brain, comorbidity, dopamine
Assessment is where it starts. ADHD is a clinical diagnosis made through a structured interview, developmental history and rating scales, not a single test. The brain part is real: ADHD is a difference in how the brain regulates attention, arousal and impulse, and it is strongly heritable rather than caused by parenting or diet. Comorbidity, the presence of more than one condition at once, is the rule rather than the exception in ADHD, as we explore in our piece on ADHD and co-occurring conditions. Dopamine is the neurotransmitter most associated with the reward and motivation differences in ADHD, which is why interesting tasks are easy and dull ones feel almost physically impossible.
E to H: executive function, focus, genetics, hyperfocus
Executive function is the umbrella term for planning, starting, organising, remembering and self-monitoring, and it is the core area ADHD affects. Focus is widely misunderstood: ADHD is not an inability to focus but a difficulty regulating it, which is why hyperfocus exists. Genetics do much of the explaining, with ADHD among the more heritable conditions in psychiatry. Hyperfocus is the state of intense, absorbed concentration on something engaging, useful when it lands on the right task and frustrating when it does not.
ADHD is not a lack of attention but a difficulty regulating it, which is why the same person can be both scattered and intensely absorbed.
I to L: impulsivity, justice, knowledge, lifelong
Impulsivity is one of the three core features, and it shows up in decisions, speech and spending as well as movement; our article on ADHD and impulsivity goes into the detail. Justice sensitivity, a strong reaction to perceived unfairness, is commonly reported by people with ADHD though it is not a formal diagnostic criterion. Knowledge of your own profile is genuinely useful, because understanding why certain things are hard reduces the self-blame that so often comes with ADHD. Lifelong is the key word for diagnosis: ADHD traits must have been present from childhood, even if no one noticed at the time.
M to P: medication, neurotype, organisation, procrastination
Medication is the most-studied intervention for ADHD and, where indicated, does much of the work on attention and impulse control, prescribed and monitored by a suitably trained clinician under the UK framework in NICE guideline NG87. Neurotype is the affirming framing: ADHD is a way a brain is wired, with strengths and difficulties, not a defect to be erased. Organisation is the practical battleground, and external systems beat willpower every time. Procrastination in ADHD is usually not laziness but task initiation difficulty, where starting is the genuine obstacle rather than effort.
Q to T: quiet ADHD, rejection sensitivity, sleep, titration
Quiet, inattentive ADHD often goes unrecognised, particularly in those who daydream rather than disrupt, which is one reason it is missed in girls and women. Rejection sensitivity, an intense emotional reaction to perceived criticism or rejection, is widely described in the ADHD community even though it is not a standalone diagnosis. Sleep is frequently disrupted in ADHD, with a brain that will not power down and a body clock that drifts later. Titration is the careful process of adjusting medication to find the right level, usually the trickiest few months and worth persevering through with your prescriber.
U to Z: undiagnosed, variety, women, working memory
Undiagnosed ADHD in adults is common, and recognition often comes late, sometimes after a child's diagnosis prompts the question. Variety is what an ADHD brain craves and what monotony denies, which has real implications for work and study. Women and girls are underdiagnosed because their presentation is often quieter and more internalised, a gap that leaves many reaching diagnosis only in adulthood. Working memory, the ability to hold information in mind while using it, is one of the executive functions ADHD hits hardest, which explains the lost trains of thought and the forgotten reason you walked into the room.
Terms the community coined
Not every useful word for ADHD comes from a clinic. The community has coined plenty of its own, and while these are not diagnostic terms, they capture experiences clinicians sometimes overlook. Body doubling describes working alongside another person, in the room or on a video call, simply because their presence makes it easier to stay on task. Doom piles are the stacks of half-sorted things that accumulate when filing them away feels impossible. Object permanence, borrowed loosely from psychology, is the community shorthand for the way things out of sight genuinely fall out of mind, which is why the open shelf works better than the closed cupboard. Time blindness names the difficulty of feeling how much time has passed or how long something will take. These are informal terms, and they would not appear in a clinical report, but they describe real features of ADHD with more precision than the textbook language sometimes manages.
A few reminders worth keeping
Beyond the vocabulary, a handful of reminders hold across the whole alphabet. ADHD is real, recognised and well-studied, not a trend. It is not caused by laziness, parenting or screens. Strategies that work tend to rely on external structure rather than willpower, because motivation in ADHD is unreliable by design. And support genuinely helps: recognition reduces shame, medication does real work where it is indicated, and the right environment turns some difficulties into strengths. The NHS information on ADHD is a reliable starting point for the basics.
What this means in practice
- ADHD is a regulation difficulty, not a simple lack of attention; the vocabulary reflects that.
- It is lifelong and strongly heritable, with traits present from childhood even when missed.
- Co-occurring conditions are common, so a confusing picture is normal rather than a sign you are wrong.
- External systems beat willpower; design your life around how ADHD actually works.
- Late and missed diagnosis is common, especially in women and in quiet, inattentive presentations.
An A to Z is a map, not a diagnosis. If reading through it kept landing close to home, that pattern is worth taking seriously. A free ADHD self-screen is an easy way to gauge whether a fuller look makes sense, and a complete ADHD assessment can tell you whether ADHD is part of your picture and what support is available. Knowing the words is useful; knowing yourself is the point.
