We are used to the fact that time on Earth is measured for centuries, years, months, and days. Each time period has its own notation. For example, a century, a day, a half year. Here we consider a concept such as “decade”, it is not used as often as some other terms, but nevertheless, its meaning is also necessary.
People who first come across this definition often wonder: the decade of the month is how many days? In this article we will consider this topic in more detail.
Origin of the word
This term comes from the Greek words dekas, which means "ten." Oddly enough, but in many other languages that are not related to Greek, there are cognates with the same meaning. There are certain assumptions on this score, the main one of which is that a word like “ten” came to us from the time when the common Indo-European language was spread.
Based on the etymology, the words “decade” and “ten” are understood as keeping score, which is a multiple of the gums - ten fingers. Previously, for some peoples, a week was equal to ten days, that is, a decade, while for others, it was five days, as, for example, in Ancient Russia. For the first time, this unit of time was applied using the French Republican calendar.
In ancient Japan, the division of the month into decades, which were then called the word "Jun", was widespread. This time dimension was introduced later in post-revolutionary France, and the ten-day period was the smallest indivisible unit of time.
From France, this concept falls into the spoken language of many peoples of European countries and becomes a measure of time, which divides the month into three parts.
What does the term “decade” mean?
A decade is a kind of group that contains ten units. This term is used mainly in relation to the month.
Based on the generally accepted definition, the decades of the month are units of time, each of which is equal to ten days. Currently, this definition is mainly used not in everyday life, but, for example, in the economic field or in statistics. It should also be noted that it is used in astrology.
Other designations
In addition, a decade sometimes means a certain event, for example, the “decade of English culture at the university” or the “decade of literature and art of the peoples of Russia”. In this case, the decades of the month are certain events that last ten days, or else a third of the month. Here this word is used in the context of a particular holiday or event of public importance.
Based on the interpretation given in Ushakov’s dictionary, the decades of the month are ten-day periods that replaced the week in the modern Soviet calendar. The time interval of ten days, which is used in the schedule of training sessions. This is also the period used in statistics and economics. The English word decade, for example, does not mean ten days, but a period of ten years. Such a designation is used in England itself and a number of countries.
How many decades in a year and how many decades in a month?
The month is 30 (31) days and, therefore, there are three decades in it.
If we take into account that the decades of the month are intervals equal to ten days, then in the year (365 days) of such decades it turns out, respectively, 36.5, rounded up to 36. In ancient Russia, in order to remove five or six extra days, we used the system of Christmas time Thus, in the year it turned out exactly 36 decades, each of which is equal to ten days.
Decades by calendar month
Accordingly, the first decade lasts from the beginning of the month, that is, from the first to the tenth, the second decade of the month is the period from 11 to 20, and the next after it from the 21st to the end of the month.
Decades in the form in which they should be are only in a number of those months in which thirty days, namely April, June, September and November, are attributed to them. In the remaining months, the 3rd decade of the month is a period that contains one extra day. The exception is the month of February, in which the last decade is less than ten days and is eight or nine days, depending on whether the leap year is or not.
