If you're referring to a single word in a text string, you can't.
Otherwise, a full description of what you are hoping to accomplish as well
as an indication of which version of Word you're using may gather some
suggestions. It's possible that a Text Box, single table cell or Word Art
will get the job done but it would help if there was more to go on.
Regards |:>)
Bob Jones
[MVP] Office:Mac