How to remove accidently added words to dictionary in web Outlook

Dear Nicole,

Good day!

Thank you for posting to Microsoft Community. We are glad to assist!

Based on your description regarding "How to remove accidently added words to dictionary in web Outlook". After thorough research and testing, I found that in Outlook for the Web supports AutoCorrect, but you can't add or remove words from the AutoCorrect list. If you have Outlook for the desktop, Go to Editing > Open in Desktop App and follow the steps on the Windows or macOS tabs. Add or remove AutoCorrect entries in Outlook - Microsoft Support

Or you may edit Words in Outlook for desktop Add or edit words in a spell check dictionary - Microsoft Support

It has been concluded that the feature you are inquiring about is not yet available In Outlook on Web. However, thank you so much for bringing this to our attention, your suggestion is very helpful, and I believe it could make the use of Outlook of Web even better. We will surely raise your concerns to our Product Development Team and hopefully this can be included in the future updates. In the meantime, we sincerely recommend you post your concern as an idea to our Outlook feedback site via Outlook · Community (microsoft.com) our Product Development Team are committed to enhancing the customer experience by continually examining suggestions to include in the design and development of future product upgrades based on your suggestions. Hopefully your suggestion will help many other people in the future. Customers’ feedbacks are always valuable for us. Thanks for your precious time and your understanding would be highly appreciated. Have a nice day!

Best regards,

Inema |Community Moderator