a traditional unit of liquid volume in Austria. The traditional seidel was equal to about 354 milliliters; this is about 12.0 U.S. fluid ounces or about 12.5 British fluid ounces. Today a seidel of beer in southern Germany and Austria is a small mug holding 300-500 milliliters, frequently the latter (1/2 liter or about 16.91 U.S. fluid ounces).