This may be my favourite etymological mix-up.The answer is, neither.
Because it begins with "sch" it was thought by some to be of Greek origin, like "school" and was therefore pronounced by some the same way, with a "sk" sound. There were others who read it as a German word, and as you may know, in German "sch" is pronounced "sh." That is where the "shedule" pronunciation comes from.
I learned this anecdote in a university course that I took on the history of English, but we were not taught how this came to be. I have come up with my own theory.
As I have mentioned several times, spelling did not used to be as consistent as we have come to regard it. I suspect that the first spelling was "cedule" and possibly sometimes "sedule" and most likely was also written "scedule." S and C together are sometimes used when one or the other would suffice. My authority for this is the word "reminisce." The mistake about the pronunciation and origin of the word might have originated from this last spelling of the word, and the "h" might have been added latter in both cases to make it consistent with the emerging orthographic conventions of German and Greek borrowings.
I have no idea if that is true or not, but it accords with what I know about the history of the English language.
According to the free dictionary, schedule is actually a Greek word in origin, and so my preferred pronunciation is vindicated. According to dictionary.com, the word is Latin in origin, totally unrelated to Greek or German, but the "sch" spelling replaces the Middle English spelling of "cedule." I leave you to make up your own minds about the true etymology. If anyone would like to quote the OED, please do so.
And you can say "schedule" any way you like. You'll still be wrong, but what are we to do, mark things in our cedule?
Melanie Kerr is the author of Follies Past: a Prequel to Pride and Prejudice
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