a sidereal month of approximately 27.32 days, the length of time taken by the moon in its orbit about the Earth to return to the same point as viewed against the background of stars
a synodic month of approximately 29.53 days, measured from a lunar phase until the return of that same phase
The average time between successive new or full moons, equal to 29 days, 12 hours, 44 minutes. Also called synodic month. a period of 28 or 29 days between one new moon and the next
The lunar month is approximately 29 53 days in length It is the average period of revolution of the Moon around the Earth with repect to the Sun, or the average interval between corresponding phases of the Moon Same as the synodical month