How To Add A Word To Outlook Dictionary : Custom Dictionary Word Addition

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Teaching Outlook to recognize a specialized term prevents constant red underlines when you type it in emails. If you have ever wondered how to add a word to Outlook dictionary, you are not alone. Many users struggle with this simple but essential task that saves time and reduces distractions.

When Outlook does not know a word, it marks it with a red squiggly line. This can be annoying, especially with industry jargon, names, or acronyms. The good news is that adding a word is quick and easy. This guide walks you through every method, from the fastest click to advanced options.

By the end, you will never have to tolerate those red lines again. Let us start with the most common way to fix this problem.

How To Add A Word To Outlook Dictionary

The simplest way to add a word is directly from the context menu. This works in Outlook for Windows, Mac, and the web version. Here is how you do it step by step.

  1. Open any email in Outlook where the word appears with a red underline.
  2. Right-click on the underlined word. A menu pops up.
  3. Look for the option that says “Add to Dictionary” or “Add to Outlook Dictionary.” Click it.
  4. The red line disappears immediately. Outlook now recognizes the word.

That is it. The word is saved in your custom dictionary. It will not be flagged again in any email or document you write in Outlook.

If you cannot find the “Add to Dictionary” option, check if the word is already in the dictionary. Sometimes Outlook does not underline words it already knows. Another reason could be that the word is misspelled. Right-click again and see if suggestions appear.

This method works for most users. But what if you want to add multiple words at once? Or what if you need to manage your dictionary? Keep reading.

Adding Words From The Spelling Check Dialog

Another way to add words is through the spelling check feature. This is useful when you are proofreading a long email. Here is how.

  1. In an open email, press F7 on your keyboard. This opens the Spelling and Grammar dialog.
  2. Outlook scans the email for errors. When it finds a word it does not know, it shows it in the dialog.
  3. Click the “Add to Dictionary” button in the dialog box.
  4. Outlook adds the word and moves to the next error.

You can also access this from the Review tab in the ribbon. Click “Spelling & Grammar” and follow the same steps. This method is great for adding several words in one session.

Adding Words In Outlook For Mac

Outlook for Mac works a little differently. The steps are similar but the menu options vary. Here is how to add a word on a Mac.

  1. Right-click (or Control-click) the underlined word.
  2. Select “Learn Spelling” from the context menu.
  3. The word is added to your dictionary.

If you want to manage the dictionary on Mac, you need to use the system-wide spelling settings. Outlook on Mac uses the macOS dictionary. To edit it, go to System Preferences > Keyboard > Text > Spelling. Then click “Edit Word List.” You can add or remove words here.

Note that changes here affect all applications on your Mac, not just Outlook. Keep that in mind if you only want the word in Outlook.

Adding Words In Outlook Web (Outlook.com)

The web version of Outlook also supports custom dictionaries. However, the feature is more limited. Here is how to add a word in Outlook.com.

  1. Open an email in the web browser.
  2. Right-click the underlined word.
  3. Select “Add to dictionary” from the menu.
  4. The word is saved to your browser-based dictionary.

Important: The dictionary in Outlook Web is tied to your browser or Microsoft account. If you switch browsers or clear cookies, the added words may disappear. For permanent additions, use the desktop version.

Managing Your Custom Dictionary In Outlook

Once you start adding words, you may want to review or edit your dictionary. Maybe you added a word by mistake. Or you want to remove old terms. Outlook allows this, but the process is not obvious.

How To Edit The Custom Dictionary File

Outlook stores custom words in a plain text file called “Custom.dic.” You can open and edit this file directly. Here is how.

  1. Close Outlook completely. The file cannot be edited while Outlook is running.
  2. Press Windows Key + R to open the Run dialog.
  3. Type this path and press Enter: %AppData%\Microsoft\UProof
  4. Find the file named “Custom.dic.” Open it with Notepad.
  5. You will see a list of words, one per line. Add new words or delete existing ones.
  6. Save the file and close Notepad.
  7. Restart Outlook. The changes take effect.

Be careful when editing this file. Do not add words with spaces or special characters. Only plain words work. Also, keep a backup in case something goes wrong.

Using The Proofing Tools In Outlook

Another way to manage your dictionary is through Outlook’s options. This method is safer for beginners.

  1. In Outlook, go to File > Options > Mail.
  2. Under “Compose messages,” click “Spelling and Autocorrect.”
  3. In the new window, click “Custom Dictionaries.”
  4. Select “Custom.dic” from the list and click “Edit Word List.”
  5. Here you can add, delete, or modify words.
  6. Click OK to save.

This interface is more user-friendly than editing the file directly. It also shows you all the words you have added so far.

Common Problems And Fixes When Adding Words

Sometimes adding a word does not work as expected. Here are the most common issues and how to solve them.

Word Still Shows Red Underline After Adding

If you added a word but it still has a red line, try these steps.

  • Restart Outlook. Sometimes the dictionary update does not apply until you close and reopen the program.
  • Check if the word is spelled correctly. Outlook may think it is a different error.
  • Make sure you added it to the right dictionary. Outlook has separate dictionaries for different languages.
  • Verify the word is not in a comment or header. Outlook only checks the main body of emails.

Cannot Find The “Add To Dictionary” Option

If the option is missing, it could be because:

  • The word is already in the dictionary. Right-click and see if the option is grayed out.
  • You are using an older version of Outlook. Update to the latest version.
  • The spelling checker is disabled. Go to File > Options > Mail > Spelling and make sure “Check spelling as you type” is enabled.

Dictionary Not Syncing Across Devices

Outlook does not sync custom dictionaries by default. Each device has its own dictionary file. To sync, you need to manually copy the Custom.dic file to other computers. Or use a cloud storage service to keep it in one place.

For Microsoft 365 subscribers, there is a feature called “Roaming custom dictionary.” It syncs across devices if you sign in with the same account. Check your Outlook settings to enable this.

Advanced Tips For Power Users

If you add many words regularly, these tips will save you time.

Adding Words In Bulk

To add dozens of words at once, edit the Custom.dic file directly. Open it in Notepad and paste your list. Each word must be on a separate line. Save and restart Outlook.

Make sure the words are lowercase unless they are proper nouns. Outlook treats them as case-insensitive by default.

Using A Shared Dictionary For A Team

In a business environment, you may want everyone to use the same dictionary. You can place the Custom.dic file on a network drive. Then configure each user’s Outlook to point to that file.

  1. Create a shared folder on the network.
  2. Copy the Custom.dic file there.
  3. On each user’s computer, go to File > Options > Mail > Spelling and Autocorrect > Custom Dictionaries.
  4. Add the shared file path instead of the local one.

This ensures consistency across the team. However, users must have write permissions to the shared file to add new words.

Adding Words With Keyboard Shortcuts

If you prefer keyboard shortcuts, you can add a word without using the mouse. After right-clicking the word, press the “A” key if “Add to Dictionary” is highlighted. Or use the arrow keys to select it and press Enter.

Some versions of Outlook allow you to press Shift+F10 to open the context menu. Then use the arrow keys to navigate.

Frequently Asked Questions

Can I Add A Word To Outlook Dictionary On My Phone?

Yes, but it depends on the app. The Outlook mobile app for iOS and Android does not have a built-in dictionary feature. Words you add on your phone may not sync to the desktop version. Use the desktop method for reliable results.

How Do I Remove A Word From Outlook Dictionary?

Open the Custom.dic file or use the Edit Word List option in Outlook options. Find the word and delete it. Save and restart Outlook. The word will be flagged again.

Does Adding A Word To Outlook Affect Other Office Apps?

Yes, because Outlook shares the custom dictionary with Word, Excel, and PowerPoint. Words added in Outlook will also be recognized in those applications. This is usually helpful, but keep it in mind.

What If I Add A Misspelled Word By Mistake?

You can remove it using the Edit Word List option. Or open the Custom.dic file and delete the word. If you cannot find it, check for typos in the file.

Why Does Outlook Not Remember My Added Words After An Update?

Sometimes updates reset the dictionary location. Check if the Custom.dic file still exists in the UProof folder. If it is missing, restore it from a backup. You can also re-add the words manually.

Final Thoughts On Adding Words To Outlook Dictionary

Now you know how to add a word to Outlook dictionary using multiple methods. The right-click method is fastest for single words. The spelling check dialog works well for proofreading. Editing the Custom.dic file is best for bulk additions.

Remember that the dictionary is shared with other Office apps. So your custom words will work everywhere. If you run into issues, restart Outlook or check the file location. With these steps, you can eliminate those annoying red underlines for good.

Take a moment to add your most used terms today. It will make your email writing smoother and more professional. No more constant corrections. Just clean, uninterrupted typing.