'Lunation' definitions:
Definition of 'lunation'
(from WordNet)
noun
The period between successive new moons (29.531 days) [syn: lunar month, moon, lunation, synodic month]
Definition of 'Lunation'
From: GCIDE
- Lunation \Lu*na"tion\, n. [Cf. Lunated.] The period of a synodic revolution of the moon, or the time from one new moon to the next; varying in length, at different times, from about 291/4 to 295/6 days, the average length being 29 d., 12h., 44m., 2.9s. [1913 Webster]