There are 20 years in a score. The word "score" can be used to mean a set or group of any 20 items, not just years.Know More
The English word "score" is likely derived from an Old Norse word, "skora," which was used to mean a notch or a tally in addition to meaning the number 20.
One of the most well-known uses of the word "score" to mean a group of 20 years is in the Gettysburg Address, in which Abraham Lincoln said, "Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal."
Martin Luther King, Jr. echoed this in the first line of his "I Have a Dream" speech: "Five score years ago, a great American, in whose symbolic shadow we stand signed the Emancipation Proclamation."Learn more about Time & Calendars
A decade is a period of 10 years. The word "decade" originates from the Greek word "dekas," which means a group of 10. The word "decade" began to be used in English to mean a period of 10 years in 1590.Full Answer >
An era is not a defined number of years. Rather, it is a period of time marked by certain characteristics, such as historical events. In geology, an era is composed of periods.Full Answer >
Unlike the Gregorian calendar, which counts years infinitely, the traditional Chinese calendar is lunisolar and rotates on a 60-year cycle. This means that the years on a Chinese calendar don't ascend in chronological order, and instead its years are named with words rather than numbers. The year names are based on a combination of one of 10 prefixes, or stems, and one of 12 suffixes, or branches.Full Answer >
Although astronomers and geologists use the word "eon" to mean 1 billion years, it is more commonly used to refer to any long, indefinite period of time. Like the words "age," "epoch" and "era," it does not refer to a set number of years.Full Answer >