Superwoman is a name used by several characters in the DC Comics universe as female versions of Superman. The Superwoman concept was created by Jerry Siegel and Joe Shuster, first appearing in Action Comics #60 (1943).
Primarily this alias is used by an evil counterpart to Wonder Woman in the Crime Syndicate, evil versions of Justice League from another universe. The first one was Lois from Earth-Three. Her Post-Flashpoint counterpart from Earth 3 is also an evil version of Lois Lane and uses the Lasso of Submission as her main weapon. She is the lover of Owlman and the stepmother of Luthor-El; Ultraman's son. During the Infinite Frontier, she was replaced in the syndicate by the amazon Donna Troy.
The name Superwoman has also been used by female counterparts to Superman; with the main ones being his longtime allies Lucy Lane, Lois Lane and Lana Lang.