Osteoclast

Large size cell, multiple well separated and round nuclei, sometimes presence of nucleolus, very abundant non-basophilic Cytoplasma with many azurophilic granules.

Its presence in the myelogram is a sign of the bone marrow origin of the sample. In clinical meaningful presentation (pancytopenia) it is, in case of very poor marrow, an indication for aplastic anemia rather than hemodiluted sample.