Origin: as if < honey + moon (? in reference to the waning of the affection of newlyweds), but ? folk etym. for ON hjūnōttsmānathr, lit., wedding-night month
See honeymoon in American Heritage Dictionary 4
Origin: Perhaps from a comparison of the moon, which wanes as soon as it is full, to the affections of a newly married couple, which are most tender right after marriage.
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