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early 15c., national emblem of England (St. George's Cross), also the badge of the Order of the Temple. Hence red-cross knight, one bearing such a marking on shield or crest. In 17c., a red cross was the mark placed on the doors of London houses inflected with the plague. Red Cross (in Muslim lands, red crescent) adopted as a symbol of ambulance service 1864 by the Geneva Conference.
Red Cross n.
An international organization that cares for the wounded, sick, and homeless in wartime according to the terms of the Geneva Convention of 1864, and now also during and following natural disasters.
A national branch of the Red Cross.
The Red Cross emblem of this organization, a Geneva cross or a red Greek cross on a white background.