A proportion used in determining the dimensional relationship of a representation to that which it represents: a world map with a scale of 1:4,560,000. b. A calibrated line, as on a map or an architectural plan, indicating such a proportion.
Yttria (yttrium oxide, Y 2 O 3), was discovered by Johann Gadolin in 1794 in a mineral called gadolinite from Ytterby. Ytterby is the site of a quarry in Sweden which contains many unusual minerals containing erbium, terbium, and ytterbium as well as yttrium.
Cold urticaria (essentially meaning cold hives) is a disorder where hives or large red welts form on the skin after exposure to a cold stimulus. The welts are usually itchy and often the hands and feet will become itchy and swollen as well. Hives vary in size from about 7mm in diameter to as big as about 27mm diameter or larger.