What does "gerrymander" mean?

Gerrymander: To divide (a State) into districts for the choice of representatives, in an unnatural and unfair way, with a view to give a political party an advantage over its opponent. [Political Cant, U. S.] Note: This was done in Massachusetts at a time when Elbridge Gerry was governor, and was attributed to his influence, hence the name; though it is now known that he was opposed to the measure. Bartlett.