1. A dark-colored compound derived from hemoglobin, formed when blood is exposed to air or certain chemical treatments; used in laboratory and medical contexts.
Usage: chiefly British spelling (American: hematin); technical/medical term; also called hematein in some contexts

Examples

• The laboratory technician prepared a haematin solution for the microscopy experiment.
• Haematin is commonly used as a stain in histological preparations.
• The oxidation of hemoglobin produces haematin, which has a characteristic brown color.
• Researchers added haematin to the sample to enhance contrast under the microscope.