Definitions for "Steampunk"
A fictional genre that looks outward from the perspective of the latter half of the 19th century with particular emphasis on the technology and economics of the more "advanced" regions of that period.
A subgenre of Alternate History; this generally deals with advanced technology in the altered past.
Steampunk is a subgenre of speculative fiction which came into prominence in the 1980s and early 1990s. The term denotes works set in (or strongly inspired by—see fantasy-world steampunk below) an era when steam power was still widely used—usually the 19th century, and often set in Victorian England—but with prominent elements of either science fiction or fantasy, such as fictional technological inventions like those found in the works of H. G. Wells, or real technological developments like the computer occurring at an earlier date.