I read a sentence in "Word by Word" by Kory Stamper which was:
Though my Twitter friend was wrong in this instance, well-researched efforts like his can turn up antedatings that we've missed.
Now, it implies that "antedatings" might be the true actual dates of the concerned events (or in this case "word's appearance" in the language). But here is how Merriam webster define the word:
a date assigned to an event or document earlier than the actual date of the event or document
Now, taking it as a guide, it can be concluded that antedate is the date prior to that event's actual happening. But it seems to contradict what Kory thinks the word means( antedate being the true date). So I think the definition as per the dictionary is at fault( the "actual" sense). Am I right?