Typos—we all make them, but some are more spectacular than others. Take dord—it’s supposed to mean density. Dord first appeared in Webster’s Third New International Dictionary for nearly all of the 1930s until an editor found it in February, 1939. It was supposed to be “D or d” but when it first went in, no one noticed there were supposed to be spaces separating the "d"s from the "or" (see The 7 Most Disastrous Typos of All Time article in Cracked.com).
My friend told one of my favorite typo stories to me about a mechanically introduced typo that nearly cost her doctorate in psychology. This was pre-word processing and my friend hired someone to type her thesis on a typewriter that she rented. What she didn’t know was that the typewriter introduced a half space after every “e” in the text. The most egregious change was to transform “therapist” into “the rapist.”
“Unfortunately,” my friend had said, “that was often the truth.”