1. an abnormal increase in the number of white blood cells in the blood, often associated with infection or disease
Usage: medical term; also spelled leucosis in British English
2. a disease in poultry and other animals caused by a virus, characterized by the development of tumors and abnormal white blood cell production
Usage: veterinary medicine; also called avian leukosis in chickens

Examples

• The patient's blood test revealed leukosis, indicating a possible infection.
• Leukosis in chickens is a serious concern for poultry farmers.
• The doctor monitored the leukosis levels to determine the appropriate treatment.
• Avian leukosis can spread rapidly through a flock if not properly managed.
• Leukosis is distinguished from leukopenia by the elevated rather than decreased white blood cell count.