How to Improve Vocabulary

‘Read more’ is not a vocabulary strategy. It's a starting point. Serious vocabulary growth comes from a small set of well-known techniques from cognitive science — spaced repetition, active retrieval, dual coding, and reading at the ‘i+1’ level. This guide walks through each one, shows how to combine them, and explains why some popular methods (highlighting, word-a-day emails) don't work.

By the end you'll have a 20-minute daily routine that adds 2–5 usable words per day — around 700–1,800 per year. That's enough, in three years, to close the gap between a general reader and a specialist.

What does ‘knowing a word’ actually mean?

Linguists divide vocabulary into receptive (words you understand when you hear or read them) and productive (words you can use naturally in speech and writing). Receptive vocabulary is 2–5× larger than productive for most adults. Both matter — but only productive vocabulary changes how you sound and think.

The core loop: encounter → retrieve → use

  Encounter (read/hear)
        ↓
   Attach meaning
        ↓
   Retrieve later (spaced repetition)
        ↓
   Use in writing/speech
        ↓
    Becomes yours

Technique 1: Spaced repetition (SRS)

Instead of re-reading a word every day, review it at increasing intervals: 1 day, 3 days, 7, 14, 30, 90. Anki, Quizlet and Memrise all implement this. A card per new word takes 8 seconds a day; 20 new words a day is a 3-minute daily commitment.

Technique 2: The ‘i+1’ reading rule

Read texts where you understand roughly 95% of the words. That leaves 5% new — an ‘i+1’ context that lets you guess most meanings from context. Below 90%, you're translating; above 98%, you're not learning.

Technique 3: Learn roots, prefixes and suffixes

Over 60% of English words are built from Latin and Greek roots. Learn 30 common roots (BENE-, MAL-, -PHOBE, -LOGY) and you unlock the meaning of hundreds of words you've never seen.

Technique 4: Dual coding

Attach an image to each new word. The dual-coded memory (verbal + visual) recalls 40% better than verbal alone in classic studies (Paivio, 1971). Anki decks with images consistently outperform text-only decks.

Technique 5: Active retrieval, not passive review

Reading a word again is passive. Writing a sentence using it, from memory, is active. Active retrieval is roughly 3× more effective per minute than passive review (Roediger & Karpicke, 2006).

Technique 6: Word families, not single words

Learn ‘ambivalent’ and you should also learn ‘ambivalence’, ‘ambivalently’, and ideally ‘ambiguity’ and ‘equivocate’. Semantic clustering keeps related words in the same neural neighbourhood.

Technique 7: Deliberate output

Force yourself to use new words in real writing — a daily journal, work email, or forum post. Words you actively use become productive vocabulary; words you only recognise remain receptive.

Technique 8: Play word games

Scrabble, Words With Friends, Wordle, and anagram puzzles reinforce spelling, letter patterns, and low-frequency words. Regular play is one of the best long-term supplements to any deliberate practice routine.

Techniques that don't work

• Highlighting text — feels productive, does nothing measurable.
• Word-a-day emails — words with no context and no retrieval.
• ‘SAT vocabulary’ lists — high-frequency test words, low real-world usage.
• Reading above your level — comprehension collapses, no learning happens.

A 20-minute daily routine

1. 5 min — SRS review (Anki, Memrise or similar).
2. 10 min — reading in your target register (news, novel, technical).
3. 3 min — capture 3–5 new words with the sentence you met them in.
4. 2 min — write one sentence using each of yesterday's words.