What it means: This is similar to 4 color black text, but the black text is built using 100% cyan, 100% magenta, and 100% yellow as well as 100% black. All black text should be built using only black, no additional colors.
Problems caused: Using more than one color to build black text can result in text that appears heavier and/or softer than intended. Normal, slight variations in registration of the 4 colors on press can cause other colors to show around the edges of the text that was intended to appear as black.
How to fix: Change the color of the text to 100% black.