jayhawker

noun

1. a native or inhabitant of Kansas (used as a nickname).
2. (sometimes lowercase) a plundering marauder, especially one of the antislavery guerrillas in Kansas, Missouri, and other border states before and during the Civil War.

n.

American English, 1858, originally “freebooter, guerrilla, Kansas irregular” (especially one who came from the North). Hence back-formed verb jayhawk “harass” (1866).