Webster’s Dictionary contained a non-existent word for 5 YEARS. How did this happen?

                                      
Webster’s Dictionary contained a definition of a non-existent word for five years.

In 1931, an abbreviations card containing an abbreviation for density marked “D or d, cont” was accidentally mixed in with the definitions cards. This confused the editors,  who mistakenly printed the notation as the word “dord,” which was classified as a synonym for density.