1722: nundinae Sep 1, 2019

Although we think of a week as 7 days, for the Romans, it was 8. This, along with their 38 weeks, left an unorganized series of 50 days in the winter—and no, the math doesn’t work out with that*. The Romans were weird—by modern standards—about time-keeping. Even with these weeks of 8 days, they were also in another sense weeks of 9, because this unorganized period of 50 days were considered, culturally speaking, to be the ninth days of the week even while they were all clustered together in the winter, hence their name ‘nundinae’. The name comes from the Latin for ‘ninth day’ (nōnus and -din-). This, along with ‘nones’ are examples of a Roman preoccupation with categorizing days by series of nines, but as explained yesterday, this was not always the same as actually counting 9.

*The nunidae was actually 50 days, meaning that the standard year was about a week and a half shy of 365 days, and this is also why February is so short. The Romans would periodically add the days in February from the 23rd; even now the leap-day is technically added as the 24th day of February, not the 29th.