According to the Help topic "What do the underlines in my document mean?":

"Word uses wavy blue underlines to indicate possible instances of
inconsistent formatting."

And the Help topic "Show or hide wavy underlines" says:

You can show or hide the wavy underlines that appear when you automatically
check spelling and grammar, or when you automatically check formatting
consistency.
.............

Formatting consistency

1. On the Tools menu, click Options, and then click the Edit tab.
2. Select or clear the Mark formatting inconsistencies check box.
--
Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
Word MVP FAQ site: http://word.mvps.org
Email cannot be acknowledged; please post all follow-ups to the newsgroup so
all may benefit.

"Thomas R" Thomas wrote in message
...
Just within the past couple of weeks every time I open a Word Document,
much
of the text is underlined with a blue squiggly line similar to the red
squiggly line found for misspellings and the green squiggly line for
grammatical errors. Right clicking displays a window with several options
including "ignore rule." Ignoring the rule usually eliminates the line at
least for one paragraph. How do I completely disable this feature? I
find
it extremely annoying.

Tom