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leukocytosis vs. leukopenia

[loo-koh-sahy-toh-sis] / ˌlu koʊ saɪˈtoʊ sɪs /
Or leucocytosis

noun

Physiology, Pathology.
  1. an increase in the number of white blood cells in the blood.

[loo-kuh-pee-nee-uh] / ˌlu kəˈpi ni ə /
Or leucopenia

noun

Medicine/Medical.
  1. a decrease in the number of white blood cells in the blood.