The Tips - Mac Kung Fu - page 262

the correct word and hit RETURN to insert it. Hit ESC again to close the list if you
don't want to choose one of the options.
Figure 40—Using OS X's word autocomplete feature
This tip works in most built-in OS X apps, such as TextEdit or Safari, but
not in Microsoft Office.
Note that in some applications where ESC is already assigned to a function,
such as in the address and search field of Safari, you'll need to hit either F5
FN +F5 on MacBooks and those with aluminum keyboards) or OPTION + ESC o
make the word list appear.