Add words to the Microsoft Word spell checker and dictionary list by right-clicking on the word you wish to add and selecting "Add to Dictionary" from the list. You can also add words to your Microsoft Word spell checker and dictionary list by creating custom dictionaries in Microsoft Word.
To create a custom dictionary in Microsoft Word 2007 or 2010, click on Proofing, then Custom Dictionaries, then When Correcting Spelling In Microsoft Office Programs. Click New from the options to create a new dictionary, then type in a name for the new dictionary. Finally, click Save to finish creating the custom dictionary. You can now add words to your custom dictionary by right-clicking on the word you would like to add and clicking Add To Dictionary from the list.
Once a custom dictionary exists, you can select it from your list of available dictionaries. Use a custom dictionary instead of the default dictionary by clicking on Proofing, then Custom Dictionary, then When Correcting Spelling in Microsoft Office Programs. Choose a dictionary from the list and click Change Default. The default dictionary appears in bold type at the top of the list; Word then uses this dictionary for spell checking documents in Word.