month

American  

[muhnth] / mʌnθ /

noun

1. Also called calendar month.  any of the twelve parts, as January or February, into which the calendar year is divided.

2. the time from any day of one calendar month to the corresponding day of the next.

3. a period of four weeks or 30 days.

4. Also called solar month.  one-twelfth of a solar or tropical year.

5. Also called lunar month.  the period of a complete revolution of the moon around the earth, as the period between successive new moons synodic month, equal to 29.531 days, or the period between successive conjunctions with a star sidereal month, equal to 27.322 days, or the period between successive perigees anomalistic month, equal to 27.555 days, or the period between successive similar nodes nodical month, or draconic month, equal to 27.212 days.

6. an unusually long period of time of indefinite length.

   I haven't seen him for months.

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idioms

1. a month of Sundays. Sunday.

month British  

/ mʌnθ /

noun

1. one of the twelve divisions ( calendar months ) of the calendar year

2. a period of time extending from one date to a corresponding date in the next calendar month

3. a period of four weeks or of 30 days

4. the period of time ( tropical month ) taken by the moon to return to the same longitude after one complete revolution around the earth; 27.321 58 days (approximately 27 days, 7 hours, 43 minutes, 4.5 seconds)

5. the period of time ( sidereal month ) taken by the moon to make one complete revolution around the earth, measured between two successive conjunctions with a distant star; 27.321 66 days (approximately 27 days, 7 hours, 43 minutes, 11 seconds)

6. Also called: lunation.  the period of time ( lunar or synodic month ) taken by the moon to make one complete revolution around the earth, measured between two successive new moons; 29.530 59 days (approximately 29 days, 12 hours, 44 minutes, 3 seconds)

7. informal a long unspecified period

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month More Idioms  

More idioms and phrases containing month

• (for months) on end
• by the day (month)

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Etymology

Origin of month

First recorded before 900; Middle English; Old English mōnath; cognate with Old High German mānōd, Old Norse mānathr. See moon

Example Sentences

The Pentagon said last month that it has reinstated credentials for seven New York Times journalists and has defended its updated rules.

From The Wall Street Journal • Apr. 10, 2026

Prices are expected to have spiked 3.4 percent last month, from 2.4 percent in February, according to a Bloomberg survey.

From Barron's • Apr. 10, 2026

From this month, the government is expanding the use of blitz courts as part of a package of measures to try to get through caseloads in England and Wales.

From BBC • Apr. 9, 2026

Of course, it must close above that level at the end of the month.

From Barron's • Apr. 9, 2026

Only a month or two before this, Marlene’s mother had become sick, and had died quite suddenly.

From "An Elephant in the Garden" by Michael Morpurgo

Related Words

• age
• date
• day
• era
• future
• generation
• hour
• life
• moment
• occasion
• pace
• past
• point
• present
• season
• second
• space
• stage
• term
• turn