Build your vocabulary#
Vocabulary is the collection of words you recognise and understand on sight. English has the largest defined vocabulary of any language — over a million words. The average English-speaking adult uses around 3,000 in everyday conversation but recognises around 50,000.
A child between six and ten learns roughly 5,000 new words a year. The average adult learns about 50.
Vocabulary matters for reading speed because every word you don’t recognise interrupts your fluency. When your eye lands on an unfamiliar word, your brain pauses, scans the surrounding sentence for context, and tries to infer the meaning. Comprehension drops. The next time you meet the same word, the same thing happens. The bigger your sight vocabulary, the fewer of these stalls you encounter — especially in unfamiliar topics, where new words come thickest.
Vocabulary is one of the better-evidenced inputs to reading speed. Unlike most “techniques” in the speed-reading literature, the link between vocabulary size and reading rate holds up well in controlled studies. Build it deliberately.
Use a dictionary#
The most useful vocabulary tool is probably already on your shelf. If it isn’t, get one — a paper dictionary, an app, or a browser bookmark to a reputable online dictionary will do.
Each time you meet a word you don’t know, or one used in an unfamiliar way:
- Spend a few seconds working out the meaning from the context of the sentence.
- Underline the word lightly and put a small mark in the margin. Note the page number at the front of the book.
- Decide whether you need the meaning now or can defer it. If the word is important to the topic, look it up immediately and write a brief definition near the word.
- When you finish the chapter or book, return to the marked words you didn’t look up and resolve them.
This is a small habit with compounding returns. Each looked-up word gets a slightly stronger memory the next time you encounter it.
Keep a new-word journal#
Looking up a word once isn’t enough to retain it. Keep a journal — a notebook, a spreadsheet, or a flashcard app such as Anki or SuperMemo — and add each new word with its definition. Review it occasionally. If you’re using flashcard software, the review is automatic.
Two small additions lock new words in faster:
- Substitute similar words. When you learn a new word, think of three near-synonyms you already know. Rewrite the sentence using one of them, then with the new word.
- Write your own sentence. Compose a fresh sentence using the new word and add it to the journal.
If you’re studying a specific topic, keep its jargon, symbols and acronyms in a separate section of the journal. Keep it next to you while you study.
Learn common prefixes and suffixes#
Many English words are built from a small set of recurring affixes. Knowing them lets you guess the meaning of an unfamiliar word without reaching for a dictionary.
| Prefix or suffix | Meaning | Examples |
|---|---|---|
| -able, -ible | capable of | portable, teachable |
| anti- | against, opposed | antisocial, antidote, anticlimax |
| -ar, -ary, -ory | relating to | auditory, similar, imaginary |
| bio- | life | biology, biography |
| co-, con-, com- | together, with | conspiracy, cooperate |
| de- | from, away | demote, depart |
| dys- | hard, ill, with difficulty | dysfunctional, dyslexia |
| ex- | out, from | express, exhale |
| geo- | Earth | geologist, geography |
| -gress | go, move | egress, progress |
| hyper- | excessive, over, above, beyond | hyperthermic, hypersensitive |
| hypo- | under, below, beneath | hypothermic, hypodermic |
| -ic | having characteristics of | linguistic |
| inter- | between | interstate, international |
| intra- | within | intrastate, intranet |
| -less | without | heartless, careless |
| -logy | study of | biology |
| macro- | large | macroeconomics, macromolecule |
| micro- | small | microchip, microscope |
| -mit, -miss | send | transmit, dismiss, missile |
| non- | not | nonsense, nonetheless |
| omni- | all | omnipotent, omnipresent, omnivore |
| peri- | around | peripheral, perimeter, periscope |
| -phon- | sound | phonetic, phonics, telephone |
| port- | carry | portable, portfolio |
| post- | after | postgraduate, postpone, posterior |
| pre- | before | preamble, preconceived, predict, preface |
| re- | back, again | redo, return, refund |
| -rupt | break | rupture, bankrupt, interrupt |
| -scope | view | microscope, telescope |
| semi- | half | semicircle, semester |
| spect- | see, look | spectacle, spectator |
| sub- | under | submarine, subversive |
| super- | over, above | supersonic |
| tele- | far | telephone, telepathy, telemetric |
| therm- | heat | thermal, thermometer, thermostat |
| trans- | across | transport, transmit, translate |
| un- | not, opposing, reverse | uncertain, unlawful, unbearable |
| under- | below, beneath | underground, underneath, underestimate |
A useful exercise: pick one affix per day and underline every word you see using it.
Understand word history#
Many English words trace back to Latin or Greek roots. Knowing the root often makes the meaning of an unfamiliar word obvious. Some examples:
| Latin word | Meaning | Examples |
|---|---|---|
| avis | bird | aviary, aviator, aviation |
| cumulare | to build up | accumulate, cumulative |
| dens, dentis | tooth | denture, dentist |
| flare, flatus | to blow | deflate, inflate |
| gerere, gestum | to carry, to bear | digest, gesture, gestation |
| judex, judicare | judge | judge, judicious, prejudice |
| locare, locus | to place, place | allocate, dislocate, local |
| putare | to think, estimate | computer, reputation |
| vita | life | vitamin, vitality, vital |
Good dictionaries include etymology — the origin of each word. Read it when you look a word up. The story behind the word makes it stick. If you keep a new-word journal, jot the etymology in alongside the definition.
More ways to grow vocabulary#
- Read more widely. New topics, new authors, occasionally material above your current level. Don’t worry about pace on stretch material — treat it as vocabulary practice.
- Follow word trails. When you look a word up and the definition contains another word you don’t know, look that one up too. Keep going.
- Use online dictionaries with audio. Hearing the word pronounced helps you recognise it in speech later.
- Software, word-a-day services and vocabulary apps. These can help, but they work best on top of the dictionary habit, not instead of it. The new words you meet during your normal reading are far more likely to be relevant to you than a generic word-a-day list.
Where this fits#
Vocabulary is one of several techniques for the Explore step of the learning process. It also directly affects reading speed — see the speed reading course for the broader picture and the fluency chapter for the matching speed-of-recognition skills.