The Logic of Time Intervals Designation in French: huit jours, quinze jours, vingt jours

The present study is devoted to the problem of the designation of time intervals in the French language in a diachronic aspect. The purpose of the study was to identify the reasons why the designation of time periods in French has no single basis. This problem has been known for a long time: at first glance, the following designations completely lack the logic: huit jours (eight days) − week, quinze jours (fifteen days) − two weeks, vingt jours (twenty days) − three weeks. However, upon closer examination, it turns out that the time periods in question were named in different periods and in accordance with different number systems adopted by different peoples, which had their influence on the formation of the French language.