1. White blood cells; cells in the blood that help the body fight infection and disease.
Usage: Plural form of leucocyte.; Also spelled 'leukocytes' in U.S. English.; Medical/scientific term.

Examples

• The doctor ordered a blood test to count the patient's leucocytes.
• Leucocytes are essential for protecting the body against bacterial infections.
• A high number of leucocytes in the blood can indicate an infection or illness.
• Different types of leucocytes, such as neutrophils and lymphocytes, have different roles in immunity.
• The immune system produces more leucocytes when the body is fighting off a virus.