The Roman Calendar: Kalends, Nones, Ides and the Days of the Week
How the Romans named months and days, what the Ides of March means, and the Latin origins of our weekday names.
Our calendar words are Roman inheritances. Knowing the Latin behind them makes the months and weekdays easier to remember.
Months
| Latin | English | Note |
|---|---|---|
| Iānuārius | January | named for Iānus, god of doorways |
| Februārius | February | linked to purification rites |
| Mārtius | March | from Mārs, god of war |
| Aprīlis | April | of uncertain origin |
| Māius | May | linked to the goddess Māia |
| Iūnius | June | linked to Iūnō |
| Iūlius | July | named for Iūlius Caesar |
| Augustus | August | named for the emperor Augustus |
| September | September | seventh month, from septem |
| Octōber | October | eighth month, from octō |
| November | November | ninth month, from novem |
| December | December | tenth month, from decem |
The names September to December mean "seventh" to "tenth" because the Roman year once began in March.
Counting days: Kalends, Nones and Ides
The Romans didn't number days 1 to 31. They counted backwards from three fixed points in each month:
| Point | Meaning | Date |
|---|---|---|
| Kalendae (Kalends) | the first day of the month | the 1st |
| Nōnae (Nones) | nine days before the Ides | the 5th or 7th |
| Īdūs (Ides) | the middle of the month | the 13th or 15th |
In March, May, July and October, the Nones fell on the 7th and the Ides on the 15th. In other months, they fell on the 5th and 13th.
Īdūs Mārtiae, the Ides of March (15 March), is famous as the day Julius Caesar was assassinated in 44 BC. The word calendar comes from Kalendae.
Days of the week
The days honoured the sun, the moon and the five visible planets, each named after a god:
| Latin | Meaning | English link |
|---|---|---|
| diēs Sōlis | day of the Sun | Sunday |
| diēs Lūnae | day of the Moon | Monday |
| diēs Mārtis | day of Mars | French mardi |
| diēs Mercuriī | day of Mercury | French mercredi |
| diēs Iovis | day of Jupiter | French jeudi |
| diēs Veneris | day of Venus | French vendredi |
| diēs Sāturnī | day of Saturn | Saturday |
Romance languages still show the Latin names, such as Italian lunedì and martedì. English uses Germanic god names for several days, but Sunday, Monday and Saturday still echo the Latin.
Useful words
- diēs — day
- mēnsis — month
- annus — year
- hodiē — today
- crās — tomorrow
- herī — yesterday
Tips
- Link months to their gods.
- Remember the Ides in March, May, July and October.
- Use the dictionary to check terms.
English Latin Dictionary
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