Entry 3 senses · 2 variants Webster, 1913 Jim-crow · Jim·-crow · IPA a. n. 01 a. For negroes only; set aside for used of negroes as a policy of racial discrimination. 1. For negroes only; set aside for used of negroes as a policy of racial discrimination. 02 n. A machine for bending or straightening rails. 1. A machine for bending or straightening rails.(Mach.) 2. A planing machine with a reversing tool, to plane both ways.