A chemical (usually ethylene glycol) added to the cooling system to prevent the coolant from freezing in cold weather. It also inhibits the formation of rust and other deposits which may clog the radiator and other cooling passageways. Its resistance to freezing is better with a mix of 50:50 with water than 100% antifreeze.
ANTIFREEZE
Meaning of ANTIFREEZE in English
English dictionary of automotive terms. Английский словарь автомобильных терминов. 2012