Eggcorn Forum

We had the second full moon in a calendar month this week. These relatively rare (every two or three year) events are called, some say, “blue moons” and give rise, supposedly, to the phrase “once in a blue moon.”

The notion that the second full moon in a month is a blue moon is a new idea. It seems to have originated in a misinterpretation, published in a popular science mag just after WWII, of older almanac designations of a blue moon as the thirteenth moon in a calendar year. The UK Phrase Finder site has one of the better explanations of the blunder.

If “once in a blue moon” describes something rare, what is “once in a new moon?” It was, the web tells us, the title of both a 1930s scifi movie and a 1990s novel. A trendy vampire novel called New Moon and the New Moon café in California both ellicit “once in a new moon” puns. When you push through this facade of media allusions and puns, however, you begin to see examples of people using “once in a new moon” as a replacement for “once in a blue moon:”

Korean pop culture forum post: “i dont get into fights with my friends very often. maybe once in a new moon ”

Adventure game forum: “Might need some help, but once in a new moon ‘You hear cawing in the distance’”

Acne forum: “ I also take Fish Oil once in a new moon.”

A new moon is not as infrequent as a blue moon. But occupying, as the new moon does, only one or two days of each lunar cycle may be reckoned in some minds as rarity. “New moon” for “blue moon” is the kind of reimaging that drives the eggcorn business. And the rhyming “new” and “blue” may be close enough in sound to trigger a mishearing.

Last edited by kem (2012-09-07 00:33:07)