British English Dictionary (Marco Pinto)

A fork of Mark Tyndall's add-on, based on David Bartlett's British Dictionary R1.19 for Firefox, Thunderbird and SeaMonkey.

British English Dictionary V4 for Firefox, Thunderbird, and SeaMonkey. A rigorously maintained, community-driven resource for accurate British English spelling.

📢 Update: As of March 2025, this dictionary fully aligns with modern -ise verb spellings (e.g., “organise”). For specific -ise/-ize variants, some verbs, and words MAY be missing or incorrectly included.

🔗 WEBSITES Website: https://proofingtoolgui.org (Proofing Tool GUI) Website: https://github.com/marcoagpinto/aoo-mozilla-en-dict (GitHub) Website: https://linkedin.com/in/marcoagpinto (LinkedIn)

🌟 Key Features:140 000+ words added since 2013 (updated to V4); • Prioritises Oxford, and Collins dictionaries as primary sources; • Supports both modern and literary vocabulary; • Compatible with Commonwealth/European English variants.

🔍 Inclusion Rules:

  1. Words verified in ≥2 authoritative sources (e.g., Oxford + Collins) (except proper nouns);
  2. Archaic terms allowed only if they don't conflict with modern usage;
  3. U.S. spellings are retained when they are widely adopted into British English (e.g., “movie”), as validated by trusted sources like Oxford or Collins. The dictionary's U.S. origins explain why many U.S. words come from it.

📥 Installation:

  1. Firefox/Thunderbird 115+ (ESR): Install directly via Mozilla Add-ons;
  2. Legacy Firefox/Thunderbird (v59 or below): • Download the .xpi file from GitHub https://github.com/marcoagpinto/aoo-mozilla-en-dict • Drag'n'drop the downloaded .xpi file into the Extensions/Dictionaries windows.
  3. Enable via right-click in an editable text area: “Languages” → “English (United Kingdom)”. 📚 Full guide: https://proofingtoolgui.org/en_installing.html

🛠 Developer Commitment:15+ years of continuous updates; • Funded personally (hosting, Oxford Premium Account access, domains); • Open-source collaboration via GitHub; • Proofing Tool GUI framework (proofingtoolgui.org) enables transparent word validation.

❓ FAQ Highlights: • Why include “movie”? → FAQ #7 https://proofingtoolgui.org/faq.html#7 • Reporting issues → FAQ #4 https://proofingtoolgui.org/faq.html#4 • Changelog → https://proofingtoolgui.org/en_GB_CHANGES.txt

🤝 Community-Driven: This project thrives on user input. If you find: • Missing Oxford/Collins words → E-mail/GitHub submissions welcome; • U.S. spellings needing removal → Provide dictionary citations; • Technical issues → Contact via e-mail/GitHub.

ℹ Ethical Notes: • No AI/automated scraping – all entries manually verified; • Archaic terms cautiously included for literary users; • Hosting costs covered privately.

This dictionary serves everyone equally – students, professionals, writers, and non-native speakers. Your feedback ensures it remains the most reliable free British English resource available.

NOTICE: I have been publicly criticised for my GB dictionary, even in front of other developers. They only point out flaws instead of suggesting new words or corrections. There are millions of words, and I can't manage them all alone.

This project is very serious. I spend hundreds of EUR every year on web hosting, domains, and a premium Oxford Dictionaries account so that everyone can enjoy quality work for free.

I am a disabled person and open-source is almost all I have left in life.

User reviews

Users praise the British English Dictionary for effectively addressing Firefox's inadequate spell check, offering an extensively comprehensive and frequently updated dictionary. It supports British English spellings preferred by many and integrates with various applications beyond Firefox. The add-on's open-source nature and the author's dedication are highly appreciated. Minor drawbacks include occasional missing words, but overall, it is viewed as an exceptional and valuable tool for British English spell checking.
Pros
  • Provides crucial spell check that Firefox lacks by default.
  • Extensively comprehensive and actively maintained dictionary with many updates and corrections.
  • Highly recommended due to continuous development and broad compatibility with multiple applications.
  • Supports British English spelling, preferred by users favoring it over American English.
  • Free and open-source with a dedicated author investing significant effort.
Cons
  • Some words are missing from the dictionary.
  • No major recurring cons reported across multiple reviews.
Recent reviews
Excellent work providing crucial spell check where it otherwise was not working.
by Ge*****, 2025-06-10

by Ug*****, 2025-01-22

by Jo*****, 2025-01-09
View all user reviews ›

Extension safety

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.

British English Dictionary (Marco Pinto) does not require any sensitive permissions.

Risk impact analysis details
  • Low This permission has no access or impact on the user's system or data, thus carrying no risk.
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.

British English Dictionary (Marco Pinto) has earned a fairly good reputation and likely can be trusted.

Risk likelihood analysis details
  • High This extension was recently updated in the past month. New updates may not be stable or safe.
  • Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
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  • Good **** ********* *** **** **** *******
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