Definition of "color line" [color line]

• A barrier, created by custom, law, or economic differences, separating nonwhite persons from whites. Also called color bar. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The Republican Party lost its most famous black supporter when Jackie Robinson, the first black to break the color line in Major League baseball and one of the country's most highly respected sports heroes, announced that he was quitting Rockefeller's Republican staff and going to work for the Democrats to help defeat Nixon, calling the Nixon-Agnew ticket "racist.""
• "Cops no longer hung in Hattie Fontenot’s bar and the color line began to dissolve, then broke like a dam."