First citation from 2nd edition of EOD, supplements to 2009.
"Quot. 1851 shows an isolated use. the expression did not come into general use until the 1920s
1851- W. Wilson, A Little Earnest Book on a Great Old Subject x. 137 (heading) Science-Fiction. Ibid., We hope it will not be long before we may have other works of Science-Fiction, as we believe such works likely to fulfill a good purpose, and create an interest, where, unhappily, science alone might fail. "
