The deliberate rearrangemant of the boundaries of congressional districts to influence the outcome of decisions. The original gerrymander was created in 1812 by Massachusetts governor Elbridge Gerry, who proposed a district for political purposes that looked like a salamander. Gerrymandering allows the concentration of opposition votes into a few districts to gain more seats for the majority in surrounding districts or the difussion of minority strength across many districts.
Source:The Center for Voting and Democracy