Definer: Word Translator, Ask AI, Popup Dictionary by Lumetrium

Stop interrupting your reading to open another tab whenever you encounter an unfamiliar word or passage. Definer 2 brings definitions, translations, pronunciation, and AI explanations directly to the page.

Double-click a word or use your preferred text-selection gesture to open the popup bubble. Explore different kinds of answers, check the surrounding context, and save useful discoveries for later—all while keeping your place.

🚀 Key Features

✅ Context-aware definitions and translations
✅ Pronunciation audio, examples, synonyms, and related words
✅ Explanations in your preferred language
✅ Follow-up conversations about selected text
✅ History with recorded results and original page context
✅ Collections for vocabulary, flashcards, and notes
✅ Export saved material or send it to Anki
✅ PDF support and compatibility with browser-based EPUB readers

🔎 Explore Multiple Sources

Different questions call for different kinds of information. Switch between dictionary entries, translations, reference articles, visual results, and explanations within the same popup.

Choose which sources appear, arrange them in your preferred order, and adjust their settings. You can add compatible websites you already use or import your own dictionary files for offline lookups. Offline Dictionary is experimental, and compatibility varies between packages.

For deeper customization, Recipes control what gets saved, Routines automate actions inside website results, and Script sources let you build interactive tools.

🤖 AI-Powered Reading and Writing Aid

When a short definition isn’t enough, ask about the passage itself. Explain an expression, summarize selected text, explore tone and implied meaning, or improve grammar and clarity. Follow-up questions let you continue the conversation, and History lets you return to it later.

Built-in AI works without a separate provider account or API key. You can also connect external providers or supported local models.

🌍 Language Learning Made Easy

Understand the meaning that fits the sentence you’re reading, with examples, translations, and pronunciation alongside it. You can look up a word in one language and read its explanation in another.

Save useful entries to Collections, add your own notes and tags, and turn discoveries into study material. Send saved items to Anki with definitions and examples arranged as cards. This requires desktop Anki and the AnkiConnect add-on.

📚 Works with Documents and Ebooks

Open reports, papers, and other documents in the included PDF reader to use the same reading features you enjoy on webpages.

For EPUB books, use a compatible browser-based reader. An EPUB reader is not included.

💡 Use Cases

For Students: Understand unfamiliar terms, explore background information, and keep useful definitions and notes together.

For Language Learners: Check meaning and pronunciation in context, save vocabulary from your reading, and export it for study.

For Professionals: Clarify difficult passages, summarize selected text, and refine grammar and wording.

For Ebook Readers: Look up unfamiliar words while reading in compatible browser-based readers, then return to your book.

❓ Frequently Asked Questions

How do I look up text on a page?
Double-click a word, use a configured selection gesture or keyboard shortcut, or choose the lookup action from the right-click menu. You can also type a query from the browser toolbar.

Can I use it with PDFs?
Yes. Open your document in the built-in PDF reader to use the extension’s reading features.

Can I use it for different languages?
Yes. Choose your preferred result languages and switch between them while reading. Available information varies by language and the service you choose.

Is it free?
Core lookup features, local History, and Collections are free. Built-in AI and translation include a limited free allowance. You can also use supported local models or connect custom AI providers with your own API keys. Optional paid memberships provide higher usage allowances, Cloud Sync, Cloud History, and higher customization limits.

Do I need an account?
Local History, Saves, and Collections work without an account. Signing in is required for account-based features such as settings synchronization and paid cloud services.

⚠ Troubleshooting Setup

If something isn’t working properly, here are a few things to try:

Reload the page. Tabs that were already open when you installed the extension may need to be reloaded.

Check your lookup gestures and shortcuts in settings.

Restart your browser. This can resolve temporary issues.

Temporarily disable other extensions to check for a conflict.

Still having trouble? Get in touch using the contact details below. Include your browser, extension version, the steps that caused the problem, and a screenshot if possible.

📧 Contact & Community

Have feedback, a feature request, or a question? Join r/lumetrium_definer on Reddit.

You can find release notes, report bugs, suggest improvements, and discuss how you use the extension.

Want to reach out directly? Email me, the developer, at definer@lumetrium.com.

For setup guides and customization examples, open Help in the extension and visit the Definer Wiki.