Gender in speculative fiction
The first known female superhero is writer-artist Fletcher Hanks's minor character Fantomah, an ageless, ancient Egyptian woman in the modern day who could transform into a skull-faced creature with superpowers to fight evil; she debuted in 1940 in Fiction Houses "Jungle Comics".
Superwoman
Superwoman is the name of several fictional characters from DC Comics. Most of them are, like Supergirl, women with powers similar to those of Superman. The name was trademarked by Detective Comics, Inc. to prevent competitors from using it. As was the practice, a publication produced solely for legal purposes was created with the title of "Superwoman". The cover was a reproduction of "More Fun Comics", with the interior being a reprint of the third issue. The first true appearance of Superwoman was in "Action Comics".