A quincunx is the X-shaped pattern of pips on the #5 face of a die. It's so-called because the Romans had a common copper coin called an as , and it was divided (monetarily, not physically) into twelve uncia . There was a bronze coin worth five uncia called a quīncunx , which is a contraction of quīnque (“five”) + uncia , and the coin had that pattern of dots on it to indicate its value. Uncia generally meant a twelfth of something. It was not just a twelfth of an as , but also a twelfth of a po
