Eosinophils, neutrophils and basophils are considered as part of
Granulocytes
WBCs are divided into two - granulocytes and agranulocytes. A granulocyte is a white blood cell that has granular cytoplasm. Eosinophils, neutrophils and basophils are granulocytes. Agranulocytes are white blood cells that lack cytoplasmic granules. Monocytes and lymphocytes are agranulocytes.
A megakaryocyte is a large bone marrow cell with a lobulated nucleus responsible for the production of blood thrombocytes (platelets).