Answer: The number 20 is called a “score” due to its historical significance in counting and notation. A “score” is an archaic term that represents 20 units or items. The word “score” has been used for centuries and can be traced back to Old English.

One of the most famous uses of the term “score” is in Abraham Lincoln’s Gettysburg Address, where he begins with “Four score and seven years ago,” referring to 87 years, or four times 20 plus seven. This usage highlights the concept of counting in scores as a way to express quantities.

The term “score” fell out of common usage in everyday language but has been retained in idiomatic expressions and historical texts. Today, it serves as a reminder of an older counting system and is often used to give a poetic or formal touch to numerical descriptions.