neutrophils - the most numerous wbc, making up about 65% of normal white count. These cells are the most important phagocytic cell in the circulation. Also called PMN (polymorphonuclear) neutrophils because of their nuclear shape. These cells spend 8 to 10 days in the circulation making their way to sites of infection etc. where they engulf bacteria, viruses, infected cells, debris and the like. They have two types of granules: the most numerous are specific granules which contain bactericidal agents such as lysozyme; the azurophilic granules are lysosomes containing peroxidase and other enzymes.