She said, “Go to Learners Dictionary dot com [=the Web site www.learnersdictionary.com] for more information.”
She arrived at 3 o'clock 'on the dot'. = She arrived 'on the dot of' 3. [=she arrived exactly at 3 o'clock]
We need some extra time to 'dot the i's and cross the t's' on the report.
(..) It comes on a few. Someone has to switch the projectors at the exact moment that one reel ends and the next one begins. You can see little dots come into the upper right corner of the screen. In the industry, we call them cigarette burns. That's the cue for a changeover. (..)1999 Fight Club