Entry 1 sense Webster, 1913 Jayhawker /jāh'-ôk-ẽr/ · Jay·hawk·er · IPA /dʒˈeɪhɔkər/ 01 n. A name given to a free-booting, unenlisted, armed man or guerrilla. 1. A name given to a free-booting, unenlisted, armed man or guerrilla.