A term from the 1890s-1930s, referring to a specific type of science fiction. The word 'Edisonade' is a play on Robinsonade, the latter coming from Robinson Crusoe, the former based on the name of Thomas Edison.
Edisonades are based around a hero-inventor; this inventor is often young, a pioneer of some sort, and poor or downtrodden, but soon to be rich and/or famous once he finishes his adventure. They were very much adventure stories, Tom Swift being a prime example (also Frank Reed and Jack Wright). Some of the first Edisonades appeared in dime novels, starting with The Steam Man of the Prairies by Edward S. Ellis (a lot of these stories involved the wild west).
You still get hero-inventors in today's SF, but the term is usually only applied to stories from before the forties' or stories written in that style.