leukocyte Definition

any of the colorless blood cells of the immune system including the neutrophils, lymphocytes, monocytes, eosinophils, basophils, and their derivatives : white blood cell

any of the blood cells that are colorless, lack hemoglobin, contain a nucleus, and include the lymphocytes, monocytes, neutrophils, eosinophils, and basophils —called also leukocyte, white blood corpuscle, white cell

any of various proteins that are encoded by genes of the major histocompatibility complex in humans and are found on the surface of many cell types (such as white blood cells); broadly : hla

a mature white blood cell having a complexly lobed nucleus and granule-containing cytoplasm and including the neutrophils, basophils, and eosinophils; especially : neutrophil