Stemmy
Add to Chrome

English vocabulary app for Chrome

Turn words you find into words you know.

Stemmy shows the meaning of the word in the sentence you are reading, not a wall of dictionary senses. Save useful English words with context, explore root words and etymology with WordDNA, and bring them back through Reviews, stories, and everyday reading.

Add to Chrome See the learning loop

Stemmy is a Chrome extension for your computer. Send yourself the link:

Stemmy is a Chrome extension. Open this page in Google Chrome.

  • Context-awareMeaning that fits the page
  • Local-firstYour wallet stays in your browser
  • Built to retainReview only what is due
Illustration: in a quarterly report the word mitigate is highlighted. Stemmy's Ghost Card shows its meaning in that sentence and its Latin roots, the word is saved, and a note confirms it was added to the Vocabulary Wallet with its sentence and page link.
01

Highlight → understand → save

Illustration
Meaning in contextPronunciationVocabulary walletSpaced reviewWallet LettersOptional sync

What is Stemmy?

Stemmy is a free Chrome extension that shows what an English word means in the sentence you are reading. Highlight a word, click the Stemmy button beside it or press Alt+Shift+D to see the meaning that fits, explore its roots with WordDNA, save it to your Vocabulary Wallet, and bring it back through spaced-repetition Reviews — without leaving the page.

  • Free Chrome extension — Free to install. No paid plan is offered today.
  • Meaning in this sentence — the sense that fits the sentence, not a generic dictionary list
  • Root words & etymology — WordDNA shows a word's roots next to its meaning
  • Vocabulary Wallet — saves each word with its meaning, the source sentence and the page link, in your browser
  • Spaced-repetition Reviews — short, resumable sessions of only the words that are due
  • 150 free AI uses — AI features need a free account (Google Sign-In or email). Each account gets 150 free AI uses in total, once; Ghost Card lookups and cloud voice draw on them.
  • No data sold — Stemmy does not collect general browsing history and does not sell personal data

Add Stemmy to Chrome — free ↗

Less collecting. More remembering.

How Stemmy works: select, understand, save, review.

Stemmy keeps discovery and practice connected, so a useful word does not disappear when you close the tab.

  1. 01
    Understand

    Get the meaning that fits the sentence—not a wall of dictionary entries.

  2. 02
    Save

    Keep the word, meaning, sentence, and source page together in your Wallet.

  3. 03
    Meet again

    Use AI Stories and Immersion to see saved words in fresh contexts.

  4. 04
    Recall

    Review due words in short sessions and choose how well you remembered.

See it work

From one word to one you keep.

Illustrated previews of the five moments Stemmy is built around. Scroll sideways to see them all.

  1. Illustration: the word mitigate highlighted in a report, with a Ghost Card showing its meaning in that sentence, its Latin roots and a play button for pronunciation.
    01Meaning in this sentenceHighlight a word, then click the Stemmy button beside it or press Alt+Shift+D. The Ghost Card shows the meaning that fits the sentence, the roots and the pronunciation.
  2. Illustration: the Vocabulary Wallet side panel with mitigate saved at the top, its sentence and source page, a category label and a search for work.
    02Saved with its sentenceEach saved word keeps its meaning, the source sentence and the page link. Search them by word or category in the side panel.
  3. Illustration: a review card for mitigate, the answer revealed, and the Again, Hard, Good and Easy buttons with Good selected before the next card slides in.
    03Short reviews of what is dueReviews cover only the words that are due. Rate each one Again, Hard, Good or Easy, and stop whenever you like.
  4. Illustration: WordDNA splitting resilient into the Latin re-, back, and salire, to jump, then showing related words salient and assail.
    04Roots and etymologyWordDNA splits a word into its roots, so one root helps with a whole family of words.
  5. Illustration: X-Ray scanning a dense article and highlighting fiduciary, contingent, attrition and covenant, listed in a panel of words worth learning.
    05X-Ray on a hard pageOn a difficult page, X-Ray shows which words are worth learning, so you can choose a few on purpose.

Every saved word has a next step

Your Vocabulary Wallet and spaced-repetition reviews.

Search your collection, see what is due, start a short review, or read a story written from your due words, from the side panel or one calm dashboard.

Reviews Short sessions; each button says when the word returnsWallet Search, categories, export as JSONStories Practise due words in context
REVIEW

Ready when you are.

3 due
1 of 3

resilient

Can you recall the meaning?

AgainHardGoodEasy
From StemmySubject Three words, back within reach
Structured review

A little recall goes a long way.

resilient /rɪˈzɪliənt/

Able to recover quickly from difficulty or change.

“The team proved resilient after a rough first quarter.”

Did you remember it? ·

  1. 02 candid
  2. 03 meticulous

Daily · 09:00 · Unsubscribe in one click

Wallet Letters · Optional

Three due words in your inbox. Answer with one click.

Switch it on and Stemmy emails you up to three words that are due for review. Click “Yes, I remembered” or “No, I forgot”, and your schedule is updated before you next open the extension.

Schedule Daily, every other day or weekly, at your hourOne click Each answer counts as a reviewYour call Off by default; every letter unsubscribes in one click

Use words, not just lists

Stories, X-Ray and Immersion: meet your words again.

AI Stories

Your words, woven into something worth reading.

Short passages written from the words in your review queue, so each one appears in a fresh context.

Immersion · Optional

Bring vocabulary back to the pages you already read.

Your saved words appear again on pages you read, with one click back to the original text.

X-Ray

Find the words on a difficult page that are worth learning.

Scan first, choose deliberately, and avoid filling your collection with noise.

Useful by default. Connected by choice.

Free account, 150 free AI uses, no paid plan.

Your wallet is stored in your browser. A free account unlocks AI meanings, with 150 free AI uses. Sync is optional. Stemmy does not collect general browsing history and does not sell personal data.

01
Stored in your browser

Your wallet, reviews and settings live in chrome.storage.local.

02
Only what a feature needs

For a meaning, the word and the sentence around it go to the AI provider; X-Ray and Immersion send page text only when you start them. Pronunciation runs when you press play, or automatically if you turn that on.

03
Sync when you choose

With sync on, your vocabulary, learning state, saved context and source URLs are stored under your account.

Read the full privacy policy

Before you add it

Questions about the free Chrome extension.

Is Stemmy free?

Yes. Free to install. No paid plan is offered today. AI features need a free account (Google Sign-In or email). Each account gets 150 free AI uses in total, once; Ghost Card lookups and cloud voice draw on them.

Do I need an account?

For AI features, yes: Ghost Card meanings and cloud voice need a free account, made with Google Sign-In or email, and each account gets 150 free AI uses in total, once. Your wallet, reviews and settings are stored in your browser either way, and sync across signed-in Chrome browsers is optional.

What is sent to the AI provider?

For a meaning, the word and the sentence around it. For X-Ray and Immersion, text from the page you started them on. Pronunciation runs when you press play, or automatically if you turn that on; your browser's own voice is the fallback.

Where are my words stored?

In your browser (chrome.storage.local), with your reviews and settings. If you switch sync on, your vocabulary, learning state, saved context and source URLs are also stored under your account, so they follow you across signed-in Chrome browsers.

What are Wallet Letters?

An optional email with up to three of your due words, daily, every other day or weekly, at the hour you choose. Each word has "Yes, I remembered" and "No, I forgot" links; clicking one records the answer and reschedules the word, so it is already updated when you next open Stemmy. Letters need a free account, are off by default, and every one has a one-click unsubscribe.

Can I export my wallet?

Yes. You can export the whole wallet as a JSON file and import it again.

Which shortcut shows a meaning?

Select a word and click the small Stemmy button that appears beside it, or press Alt+Shift+D. You can also click the Stemmy icon in the toolbar with a word selected. The card shows the meaning that fits the sentence; "More about this word" adds synonyms and WordDNA roots.

Ready when curiosity strikes

Your next useful word is already out there.

Give it a place to grow.

Add Stemmy to Chrome

Stemmy is a Chrome extension for your computer. Send yourself the link:

Stemmy is a Chrome extension. Open this page in Google Chrome.