First of all let’s get the most obvious definition out of the way. Merriam-Webster offers the most complete, if not the most interesting: “the earth’s natural satellite that shines by the sun’s reflected light, revolves about the earth from west to east in about 29¹/₂ days with reference to the sun or about 27¹/₃ days with reference to the stars, and has a diameter of 2160 miles, a mean distance from the earth of about 238,900 miles, and a mass about one eightieth that of the earth.”

And the second most common definition, moon the verb: “expose one’s buttocks to (someone) in order to insult or amuse them.”

Leaving visions of that aside for the moment, what’s more intriguing than the mere definitions is the concept of moon as it is expressed through various moon idioms. The moon is everything and it’s infinity. It can be surprisingly attainable as well as wholly unreachable.

If you are over the moon, you’re wildly happy. Maybe someone you love has just surprised you with a marriage proposal or you just got a dream job you never expected to get. But if you bark at the moon, bay at the moon, or cry for the moon you’re seeking something you’re not likely to get. 

Shooting for the moon implies a long shot, maybe betting on the horse in the race with the longest odds. Doing so means you’re reaching for the moon. You might promise the moon, in which case you are likely offering the moon on a stick.

Many moons ago is a long time in the past and a labor of many moons is going to be a long time to come. If you are mooning away the day, you’re likely not doing much and you could be chided to keep out of the moon. Mooning over movie stars or sports heroes is likely as unproductive.

The moon has served as a symbol through the ages. In Greek mythology the crescent moon represents the feminine moon goddess Selene, goddess of female empowerment. Roman mythology views the crescent moon at a bow, used by Diana, goddess of the hunt. In China, the moon is the ying to the sun’s yang, the female moon and the male sun providing a balance.

In most cases, the symbolism of the moon is distinctly feminine. The University of Michigan Dictionary of Symbolism has this to say:

“The moon is a feminine symbol, universally representing the rhythm of time as it embodies the cycle. The phases of the moon symbolize immortality and eternity, enlightenment or the dark side of Nature herself. It might reflect inner knowledge, or the phases of man’s condition on earth, since it controls the tides, the rains, the waters, and the seasons. It is the middle ground between the light of the sun and the darkness of night, and thus often represents the realm between the conscious and the unconscious. In astrology, the moon is a symbol of the soul, and in the horoscope it determines the subject’s capacity for reflection and adaptation. It also provides analogy for the stages of human development: the new moon is infancy, the crescent is youth and adolescence, the full moon is maturity and pregnancy, and the waning moon represents the decline of life, sleep.”

And then there’s: