synodic month
Noun
Meaning
the period between successive new moons (29.531 days)
Source: WordNetSynonyms
Hypernyms
Examples
Accordingly, for convenience, a long-term average length, identical to the mean synodic month of ancient times (also called the molad interval) is used.
Additionally, the synodic month does not fit easily into the year, which makes accurate, rule-based lunisolar calendars complicated.
Due to the eccentricity of the lunar orbit around Earth (and to a lesser degree, the Earth’s elliptical orbit around the Sun), the length of a synodic month can vary by up to seven hours.
A synodic month is longer than a sidereal month because the Earth-Moon system is orbiting the Sun in the same direction as the Moon is orbiting the Earth.
A lunation or synodic month is the mean (average) time from one new moon to the next.
Although there're many stories to interpret the intercalation, but a period of 22 or 23 days is always 3/4 synodic month.