basophil

This term describes a specialized leukocyte characterized by its affinity for basic dyes, which results in a distinct blue-purple coloration under a microscope. It functions as a critical component of the immune system, specifically mediating allergic reactions and inflammatory responses by releasing chemical mediators. As a biological term for a specific cell type, it follows standard English countability rules for cells, though it is most frequently encountered in medical contexts referring to the basophil count within a differential white blood cell analysis.