Vocabulary & Word Knowledge

Vocabulary is the words a child knows. Word knowledge is how well they know them — and that matters more than the count. Knowing a word properly means knowing what it means, when you would use it, what other words it sits near, how it changes (help, helpful, unhelpful) and how it sounds and looks written down.

Most children understand many more words than they use. That gap is normal. A word usually has to be met several times, in different situations, before a child starts using it themselves.

Vocabulary is also not the same as intelligence, and not the same as how much a child has to say. Children arrive with different experiences, different interests and sometimes more than one language. A child who speaks another language at home may know fewer English words and more words overall than a classmate.

The Department for Education's reading framework describes reading comprehension as depending on two things together: being able to read the words on the page, and understanding the language they are made of. A child can decode a page perfectly and still not know what it means, because too many of the words are unfamiliar.

It works the same way in conversation, in maths problems, in instructions and in friendships. Words are how children get at what is going on around them and how they say what is going on inside them.

• Words are learned mostly from conversation and stories, not from lists.
• Children need to meet a word several times before it sticks, and in more than one setting.
• Understanding a word comes before using it — often by a long way.
• Talk that goes back and forth builds more than talk that is one-directional.
• Books introduce words that rarely come up in everyday speech, which is much of why shared reading matters.
• Children learning more than one language build vocabulary across all of them; a lower English score can simply mean less English so far.

Speech and Language UK's Ages and Stages descriptions give a helpful feel for typical development. They describe ranges, not deadlines — children vary enormously and still end up fine.

None of these on its own means anything is wrong. They are simply worth noticing, and worth mentioning to school if you see them often.

• Reaches for "thing", "stuff" or "that one" rather than the word they want.
• Uses a word that is nearly right — "the bit that goes round" for wheel.
• Understands the story when you read it, but cannot retell it with much detail.
• Asks what words mean often, or stops asking and looks lost instead.
• Struggles to explain something they clearly understood.
• Avoids books or conversations pitched slightly above them.
• Talks confidently about the things they love and much less about anything else.

• Word lists to learn by heart — words learned that way rarely turn up in real use.
• Stopping the story to test every hard word; a quick aside keeps the reading alive.
• Correcting a nearly-right word rather than supplying the right one warmly.
• Treating a home language as competition for English. It is not, and dropping it costs a child something real.
• Reading a list like this and concluding your child has a condition. A checklist cannot tell you that.

It is reasonable to ask for advice if difficulty with words is persistent, shows up across home and school, and is affecting how your child learns, plays or feels.

• Start with your child's teacher, with examples of what you notice.
• The school's SENDCO can look at whether adjustments are needed and whether school sees the same picture.
• Your GP or health visitor can refer to NHS speech and language therapy; in many areas families can self-refer.
• A hearing check is worth doing if it has been a while — hearing affects word learning directly.

1. Department for EducationProfessional guidance
   The reading framework: teaching the foundations of literacy (2021, updated 2023)

   Sets out the Simple View of Reading — comprehension depends on word reading and language comprehension together — and a substantial section on developing talk. It is about teaching practice, not about any particular vocabulary programme.

2. Department for EducationStatutory guidance
   SEND Code of Practice: 0 to 25 years (2015)

   Names communication and interaction as one of the four broad areas of SEN and sets out the graduated approach — assess, plan, do, review — that schools must follow.

3. Department for EducationStatutory guidance
   Early years foundation stage statutory framework (current version)

   Communication and language is one of three prime areas; providers must give children a language-rich environment and back-and-forth conversation.

4. Education Endowment FoundationResearch summary
   Oral language interventions (Teaching and Learning Toolkit)

   Rates oral language approaches — including explicit vocabulary teaching and structured discussion — as high impact for very low cost, based on extensive evidence. The Toolkit is revised periodically; check the live page for the current figure rather than quoting an older one.

5. Education Endowment FoundationResearch summary
   Preparing for Literacy: improving communication, language and literacy in the early years (2018)

   Recommends high-quality adult–child interaction and deliberate vocabulary development, and notes the recommendations may also apply to older pupils who have fallen behind.

6. Education Endowment FoundationResearch summary
   Improving Literacy in Key Stage 1 (2017, updated)

   Places language capability — vocabulary, listening and structured talk — among the foundations of early reading and writing.

7. Education Endowment FoundationResearch summary
   Improving Literacy in Key Stage 2 (2017, updated 2021)

   Recommends teaching a small number of useful words in depth, teaching pupils how words work — including roots, prefixes and suffixes — and using structured discussion to build comprehension.

8. Education Endowment FoundationResearch summary
   Getting to the root of vocabulary instruction (blog) (2024)

   Discusses morphology — teaching how words are built — as a promising approach. Promising is the right word: the UK trial base here is still small.

9. Royal College of Speech and Language TherapistsProfessional guidance
   Clinical information: developmental language disorder (DLD)

   Reports that DLD affects around 7.6% of children — roughly two in a class of thirty. DLD affects understanding and using language and is diagnosed by a speech and language therapist, not inferred from a low vocabulary score.

10. NICEProfessional guidance
    Early years: promoting health and wellbeing in under 5s (QS128), quality statement 2: speech and language (2016)

    Notes that children with communication difficulties are at increased risk of social, emotional and behavioural difficulties. It concerns early identification in the under-fives, not primary-age vocabulary teaching.

11. Clegg, Law, Rush, Peters & RoulstoneResearch evidence
    The contribution of early language development to children's emotional and behavioural functioning at 6 years (ALSPAC), Journal of Child Psychology and Psychiatry (2015)

    UK birth-cohort study finding an association between early language and later emotional and behavioural functioning. Observational, so it shows a link, not that improving vocabulary improves behaviour.

12. Dixon, Thomson & FrickeResearch evidence
    Evaluation of an explicit vocabulary teaching intervention for children learning English as an additional language in primary school, Child Language Teaching and Therapy (2020)

    UK primary evaluation showing explicit vocabulary teaching benefits pupils learning English as an additional language.

13. Murphy & Unthiah (University of Oxford, for the EEF and the Bell Foundation)Research summary
    A systematic review of intervention research examining English language and literacy development in children with EAL (2015)

    Review of what helps pupils learning EAL. A lower score on an English-only vocabulary test is a measure of English exposure, not of ability or of a language disorder.

14. CushingResearch evidence
    Word rich or word poor? Deficit discourses, raciolinguistic ideologies and the resurgence of the 'word gap' in England's education policy, Critical Inquiry in Language Studies (2022)

    A UK critique of how the 'word gap' has been used in English education policy. Worth reading alongside the vocabulary literature, not instead of it.

15. Sperry, Sperry & MillerResearch evidence
    Reexamining the verbal environments of children from different socioeconomic backgrounds, Child Development (2019)

    Found that the widely quoted '30 million word gap' figure (Hart & Risley, 1995, USA) does not replicate. The figure is still repeated in training materials; it should not be treated as established fact.

16. Speech and Language UKProfessional guidance
    Ages and Stages

    Qualitative descriptions of typical communication development by age band. Ranges, not norms — individual variation is expected.

17. NHSProfessional guidance
    Help your child learn to talk

    Plain-language NHS advice for families on everyday talk. Practical guidance rather than a research source.