1. A dark blue or black synthetic dye used in inks, paints, textiles, and microscopy staining.
Usage: Also spelled nigrosine.; Technical/industrial term.

Examples

• The microscope slide was prepared using nigrosin to highlight the bacterial cells.
• Nigrosin is commonly used in the formulation of black printing inks.
• The textile manufacturer added nigrosin to achieve a deep, uniform black color.
• In negative staining techniques, nigrosin helps contrast biological specimens against the background.