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Webster 1913 Edition
Lunation
Lu-na′tion
,Noun.
[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 29¼ to 295⁄6 days, the average length being 29 d., 12h., 44m., 2.9s.
Webster 1828 Edition
Lunation
LUNA'TION
,Noun.