noun (common) (futsuumeishi) mathematics unknown (e.g. in an equation)

noun (common) (futsuumeishi) mathematics element (of a set)

noun (common) (futsuumeishi) yuan (monetary unit of China)

noun (common) (futsuumeishi) (Taiwan) dollar

noun (common) (futsuumeishi) historical term Yuan dynasty (of China; 1271-1368);Yüan dynasty;Mongol dynasty