Question 1

What is QuickDef?

Accepted Answer

QuickDef is a Chrome extension that provides instant, AI-powered word definitions without leaving the page you're reading. Double-click any word — on any webpage or PDF — and a definition appears in a small popup overlay. For English language learners, it generates context-aware explanations in plain English calibrated to A2–B1 CEFR level. A traditional dictionary mode is also available for complete entries with phonetics and audio.

Question 2

What is the best Chrome extension for looking up word definitions?

Accepted Answer

QuickDef is a Chrome extension that lets you double-click any word to get an instant AI-powered definition without leaving the page. It works on PDFs, academic papers, and any webpage. For English learners, it generates plain-language explanations based on the sentence context — so the definition matches exactly how the word is being used, not a generic list of all possible meanings.

Question 3

Does QuickDef work on PDFs?

Accepted Answer

Yes. QuickDef works on PDFs and academic papers, where most dictionary extensions fail. Double-click any word in a PDF and get an instant definition in a popup — without switching tabs or copying text elsewhere.

Question 4

What is the difference between QuickDef Simple mode and Full mode?

Accepted Answer

Simple mode uses AI (GPT-4o-mini) to generate a plain-language definition based on the sentence context — ideal for language learners who need accessible explanations. Full mode pulls traditional dictionary definitions from the Free Dictionary API, including all parts of speech, phonetic transcription, and audio pronunciation — for users who want the complete dictionary entry.

Question 5

How much does QuickDef cost?

Accepted Answer

QuickDef is free to start with no credit card required. The free tier includes 10 AI definitions per day and up to 50 saved words — dictionary mode is always unlimited. Premium is $3.99/month or $29.99/year (about $2.50/month) and includes unlimited AI definitions and unlimited saved words.

Question 6

Who is QuickDef designed for?

Accepted Answer

QuickDef is designed for anyone who reads regularly in English and encounters unfamiliar words — especially English language learners (ELLs), students reading academic content, and professionals working in English as a second language. The AI definitions are calibrated to A2–B1 CEFR level, making them accessible to intermediate learners without being condescending.

Question 7

How does QuickDef's AI definition work?

Accepted Answer

When you double-click a word, QuickDef sends both the word and the surrounding sentence to GPT-4o-mini. The AI returns a definition that matches how the word is being used in that specific sentence — not a generic dictionary entry. This context-awareness means you get the right meaning immediately, without having to choose from a list of possibilities.

Question 8

Does QuickDef save words for later review?

Accepted Answer

Yes. QuickDef saves words along with the sentence they appeared in, not just the word itself. Free accounts can save up to 50 words; Premium accounts have unlimited saving. Saved words are synced to your account and accessible across devices.

Question 9

Do I need to create an account to use QuickDef?

Accepted Answer

No. QuickDef supports anonymous sign-in — your first use automatically creates a private account with no email or password required. You can use QuickDef and save words immediately. Full sign-up is available if you want persistent, named access.

Question 10

Which browsers does QuickDef work in?

Accepted Answer

QuickDef works in Chrome and all Chromium-based browsers (Brave, Edge, Opera, Arc). Firefox and Safari are not currently supported.

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