Month

month   (mŭnth)    n.   A unit of time corresponding approximately to one cycle of the moon's phases, or about 30 days or 4 weeks. Abbr. mo. One of the 12 divisions of a year as determined by a calendar, especially the Gregorian calendar. Also called calendar month. A period extending from a date in one calendar month to the corresponding date in the following month. A sidereal month. A lunar month. A solar month. [Middle English moneth, from Old English mōnath; see mē-2 in Indo-European roots.] Usage Note: The singular month, preceded by a number and a hyphen, is used as a compound attributive: a three-month vacation. The plural possessive form without a hyphen is also possible: a three months' vacation.

Month

Month\, n. [OE. month, moneth, AS. m[=o]n?, m[=o]na?; akin to m[=o]na moon, and to D. maand month, G. monat, OHG. m[=a]n[=o]d, Icel. m[=a]nu?r, m[=a]na?r, Goth. m[=e]n[=o]?s. [root]272. See Moon.] One of the twelve portions into which the year is divided; the twelfth part of a year, corresponding nearly to the length of a synodic revolution of the moon, -- whence the name. In popular use, a period of four weeks is often called a month.

Note: In the common law, a month is a lunar month, or twenty-eight days, unless otherwise expressed. --Blackstone. In the United States the rule of the common law is generally changed, and a month is declared to mean a calendar month. --Cooley's Blackstone.

A month mind. (a) A strong or abnormal desire. [Obs.] --Shak. (b) A celebration made in remembrance of a deceased person a month after death. --Strype.

Calendar months, the months as adjusted in the common or Gregorian calendar; April, June, September, and November, containing 30 days, and the rest 31, except February, which, in common years, has 28, and in leap years 29.

Lunar month, the period of one revolution of the moon, particularly a synodical revolution; but several kinds are distinguished, as the synodical month, or period from one new moon to the next, in mean length 29 d. 12 h. 44 m. 2.87 s.; the nodical month, or time of revolution from one node to the same again, in length 27 d. 5 h. 5 m. 36 s.; the sidereal, or time of revolution from a star to the same again, equal to 27 d. 7 h. 43 m. 11.5 s.; the anomalistic, or time of revolution from perigee to perigee again, in length 27 d. 13 h. 18 m. 37.4 s.; and the tropical, or time of passing from any point of the ecliptic to the same again, equal to 27 d. 7 h. 43 m. 4.7 s.

Solar month, the time in which the sun passes through one sign of the zodiac, in mean length 30 d. 10 h. 29 m. 4.1 s.

month 

Month

Among the Egyptians the month of thirty days each was in use long before the time of the Exodus, and formed the basis of their calculations. From the time of the institution of the Mosaic law the month among the Jews was lunar. The cycle of religious feasts depended on the moon. The commencement of a month was determined by the observation of the new moon. The number of months in the year was usually twelve (1 Kings 4:7; 1 Chr. 27:1-15); but every third year an additional month (ve-Adar) was inserted, so as to make the months coincide with the seasons. "The Hebrews and Phoenicians had no word for month save 'moon,' and only saved their calendar from becoming vague like that of the Moslems by the interpolation of an additional month. There is no evidence at all that they ever used a true solar year such as the Egyptians possessed. The latter had twelve months of thirty days and five epagomenac or odd days.", Palestine Quarterly, January 1889.

month

In addition to the idiom beginning with month, also see by the day (month); (for months) on end.

month

a measure of time corresponding or nearly corresponding to the length of time required by the Moon to revolve once around the Earth

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