不ふ凍とう剤ざいMeanings1nounantifreeze; antifreezing agentTechnical term for a substance added to a liquid to lower its freezing point, used in engines, cooling systems, etc.冬ふゆは車くるまのラジエーターに不ふ凍とう剤ざいを入いれる必ひつ要ようがある。In winter, you need to put antifreeze in the car's radiator.