You're confusing three separate features (although Micorosft fosters the
confusion by giving them all names that start with "Auto").
AutoFormat has nothing to do with this, although it is annoying in its own
way (see http://www.yqcomputer.com/
The feature that involves a trigger (the F3 key, or the Enter or Tab key if
the entry's name is unique after four characters or more) is called
"AutoText". It's accessed through the Insert > AutoText menu. See
The feature that makes replacements without any separate trigger (just
typing a space or punctuation after a recognized item) is called
"AutoCorrect". It's accessed through the Tools > AutoCorrect Options menu.
In either feature, Word should not recognize characters that are part of a
large word as candidates for replacement. Is that what's happening?
Microsoft Word MVP FAQ: http://www.yqcomputer.com/
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