Month and Moon Are the Same Word
A month is a division of the year. The word comes from moon, because months once tracked the lunar cycle exactly.
A month is one of the twelve divisions of the year. The word is *moon* with a different ending, and originally a month was exactly one lunar cycle of about 29.5 days. Twelve of those come to 354 days, eleven short of a solar year, which is why calendar months had to be stretched and no longer match the moon at all. Islamic calendars still use true lunar months, which is why Ramadan moves through the seasons.
- A division of the year. *Three months.*
- Lunar month — one moon cycle. *A lunar month.*
- Moon — the same word. *A full moon.*
- Monthly — once a month. *A monthly meeting.*
- Old English — *monath*, month. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | month | One month. |
| Plural | months | Six months. |
| Adjective | monthly | A monthly bill. |
| Related | moon | The moon. |
| Old English | monath | Month. |
- The lease runs for six months.Time.
- A lunar month is about 29.5 days.Astronomy.
- Month and moon are the same word.Etymology.
Why the months are uneven
- Twelve lunar months total 354 days, eleven short of a solar year
- Roman calendars stretched months to fill the gap
- February absorbed the shortfall and stayed short
- July and August were named after Julius and Augustus Caesar
- September to December still mean seventh to tenth, from an older ten-month year
Old English *monath*, from *mona*, moon, from a Germanic root shared with German *Monat*.
Why is September the ninth month when it means seventh?
The Roman year originally began in March. When January and February were added at the start, the numbered names slipped by two.
Are month and moon related?
Yes, directly. A month was originally one complete cycle of the moon.