Unless you purposely misspelled the word MILLENIUM in your question, the correct spelling is millennium (2 n's, not 1).

• U. S. English: http://dictionary.reference.com/browse/millennium
• British English: http://dictionary.cambridge.org/dictionary/british/millennium

You should install a dictionary instead of relying on the built-in dictionary (U. S. English Firefox only). It appears that you do not have a dictionary installed: https://addons.mozilla.org/en-US/firefox/language-tools/

• Also see: http://support.mozilla.com/en-US/kb/Using+the+spell+checker
• Also see: http://kb.mozillazine.org/Spell_checking

That correct spelling is shown in the U. S. English dictionary when right-clicking on the misspelled word. I do not have the British English dictionary installed.

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I suppose I just misunderstood some of what google has told me.

nevertheless, I've had many proper spelled words be called wrong, so I'm rather thankful for the dictionary app, I suspect it will help me quite a bit.

Makaub:

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Thanks

Be sure to thoroughly read the articles concerning spell checking. You can add words that are not in the Add-on dictionary (your personal dictionary). You can also edit words added to your personal dictionary.

There are some Google results using the spelling that you originally indicated being used for games, hotels, foundations, etc., but that spelling is actually not proper. When searching for those using an improper spelling, you must search by their spelling of the word. For correct spelling in acceptable spoken or written language, always consult a dictionary.

I have a problem with spellchecker, too. I can't remember when it began, but it is saying words are misspelled when they are not. For example, "few." That's just the most recent example I can think of. It's become a daily issue. I actually came to the forum to search for a way to turn it off, it's become such an annoyance. I am tired of clicking "add to dictionary" just to get the red off my page.

Do you have a dictionary installed and selected?

You can see which dictionary is selected if you right-click in a text area and open the Languages submenu.

• Open the "Add Dictionaries" link to install a dictionary if you do not have one.
• Make sure that [X] "Check Spelling" in the right-click context menu is check-marked.

You can enable or disable spell checking globally:

• Tools > Options > Advanced : General: Browsing: "Check my spelling as I type"

You can look here for dictionaries:

• https://addons.mozilla.org/firefox/language-tools/

• https://support.mozilla.org/kb/Using+the+spell+checker