Definer: Word Translator, Ask AI, Popup Dictionary

Name: Definer: Word Translator, Ask AI, Popup Dictionary
Rating: 4.5775 (142 reviews)
Author: Lumetrium

By: Lumetrium

Use AI translator and dictionary online with AI search to spell check sentences & learn new words

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Features & Capabilities

Definer brings real-time AI translation, an instant dictionary, pronunciation, and context-aware definitions directly into your browser. With support for 487+ languages, it lets you translate text on any page, identify languages, and compare results from multiple engines, all while staying in your workflow. It also integrates with Gmail for seamless translations and provides custom hotkeys, themes, and an accessible study aid for language learners, students, and professionals.

Real-time translation across 487+ languages
Built-in dictionary with definitions, synonyms, antonyms, and IPA pronunciation
Language auto-detect, multiple translation engines (Google, DeepL, Bing)
In-page translation, Gmail translation, and browser-wide usage
Custom hotkeys, themes, and activation options

User Growth & Download Statistics

Add-on AI Education

By:

Daily users:

Rating:

Version:

1.16.9 Last updated: 2026-07-08

Version code:

6345192

Creation date:

2021-06-14

Risk:

Permissions:

Host permissions:

*://*/*

Content scripts matches:

<all_urls>
*

Size:

6.87MB

Email:

de*****@lumetrium.com

URLs:

Website ,Privacy policy

Full description:

Source:

Firefox Add-ons Store

Data ingested on:

2026-07-11

Compare stats and ranking:

Ranking

# 1,527 ▲ 8

Other rankings

#65 in Language Support ▼ 1

#165 in Social & Communication ▼ 3

#174 in Search Tools ▲ 4

#4 in define keyword 12

#11 in defi keyword 32

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Other platforms

Definer - Word Translator, Ask AI, Dictionary Extension (v1.16.9)

50,000 4.78

(388)

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.

Developed by:

Lumetrium

Firefox Add-ons Store

https://addons.mozilla.org/firefox/addon/lumetrium-definer/

Email:

de*****@lumetrium.com

Website:

https://www.reddit.com/r/lumetrium_definer/

Permission Change History

2025-04-29: Version 1.8.7 → 1.8.8

Add Permissions: scripting

2025-01-21: Version 1.4.6 → 1.5.0

Add Optional host permissions: <all_urls>

2024-12-21: Version 1.2.14 → 1.4.0

Add Host permissions: *://*/*

Add Permissions: declarativeNetRequest identity

Remove Permissions: webRequest webRequestBlocking <all_urls>

User Reviews

Reviewers praise Definer for speed, customization, and convenience. It is seen as a fast, unobtrusive, all-in-one tool with a broad feature set for translations and lookups. Some note requests for a translation panel/copy workflow and mention a WordReference source issue, but overall it's regarded as top-tier and reliable.

Pros

Highly customizable with options that can be stripped back or tailored to exact needs
Fast, clean, unobtrusive and background-friendly
Feature-rich and versatile, with translation, lookup, search, and more in one extension
Convenient and easy to use, delivering value without slowing down the browser

Cons

Recent reviews

Good Extension!!

by Bu*****, 2026-06-21

I was looking for something like Rikaikun for other languages and found this brilliant open-source extension. Really impressed at how clean, simple and fast it is - just double-click a word and you get a dictionary definition, translation, and other handy things. I can tell it's really going to help me a lot with language learning. Small request: Wiktionary would be awesome as a built-in source! It was easy to add it as a custom source though, so that's really cool too.

by Fi*****, 2026-06-11

Awesome!.

by DA*****, 2026-05-17

View all user reviews ›

Is Definer: Word Translator, Ask AI, Popup Dictionary Safe?

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Definer: Word Translator, Ask AI, Popup Dictionary requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details

Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
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Risk likelihood

Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

Definer: Word Translator, Ask AI, Popup Dictionary is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details

High This extension was recently updated in the past month. New updates may not be stable or safe.
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