In severe cases, the viral infection causes a high fever, bleeding into the skin, and necrosis (death) of cells in the kidney and liver. The damage done to the liver from the virus results in severe jaundice which yellows the skin. Hence, the yellow in yellow fever..
filter definition: The definition of a filter is something that separates solids from liquids, or eliminates impurities, or allows only certain things to pass through. (noun) A Brita that you attach to your water faucet to remove impurities from you...
air filter - a filter that removes dust from the air that passes through it. air cleaner. filter - device that removes something from whatever passes through it. filter tip - an air filter on the end of a cigarette; contains material that filters the smoke. ventilator - a device (such as a fan) that introduces fresh air or expels foul air.