5 Words that Come from the Moon

Fifty years ago, Neil Armstrong and Buzz Aldrin became the first people to walk on the moon. Unfortunately, all they brought back were some rocks.

But the moon has given us many things, including several words! So let’s celebrate this landmark in space exploration by looking at the etymology of “moon,” plus five words it has inspired.

Moon Etymology

The word “moon” has a long history, which is unsurprising given that it’s a massive glowing orb in the night’s sky that has been around for longer than human language. We can, however, trace it back to both the Middle English mone and the Old English mona.

Further back, it may come from the Proto-Indo-European term *me(n)ses- and the root *me-, meaning “measure.” Here, we see how people have used the waxing and waning of the moon to measure the passage of time since… well, since we’ve had any notion of time passing.

Another term we may want to look at is “lunar,” an adjective meaning “related to the moon.” This comes from the noun luna, an old-fashioned word with origins in the PIE root *leuk-, meaning “light” or “brightness.” And here we see the importance of the moon as a source of light at night.

But how have these terms influenced modern English? Let’s take a look.

5 Words that Come from the Moon

There are many, many words with a connection to our lunar neighbor. And we won’t even touch on figures of speech such as over the moon and once in a blue moon. But we will look at five of our favorite moon-derived terms to see where exactly they come from.

1. Moon as a Verb

As well as a noun, “moon” has picked up two key uses as a verb over the years:

1. To act absent-mindedly, often through distraction (e.g., to “moon over” someone or to “moon around” the house when you have nothing to do).
2. To expose one’s buttocks as a joke or insult.

The first of these is probably related to the word “moonstruck,” which reflected an old belief that the moon could affect people’s behavior (more on that below). The second comes from the fact that buttocks can be pale and round, much like a certain feature of the night’s sky. We hope learning this doesn’t prompt you to see the moon as a big sky buttock, though.

2. Month

Originally, a “month” was literally the time between one new moon and the next one. As such, we can find connections between “moon” and “month” in many European languages. In fact, the PIE term *me(n)ses- above may have originally meant both “moon” and “month.”

Another word we get from “moon” is “Monday,” which literally means “day of the moon.” We also see this in the German Montag, as well as the French lundi, the Spanish word lunes, and the Italian term lunedi.

3. Menstruation

Moving on from “month,” we have a monthly cycle: menstruation. In fact, “menstruation” and “menses” come from Latin and Greek words meaning “month” (mensis) and “moon” (mene).

Some people also believe their menstrual cycles sync up with the lunar cycle. However, there is no scientific evidence for this, so it is probably a myth.

4. Lunatic

Above, we mentioned the old belief that the moon can affect people’s behavior. We see this most clearly in the word “lunatic,” which now refers to someone who behaves erratically.

Not that long ago, though, “lunatic” was a word for someone suffering from mental illness. And some people still believe the moon can affect our behavior. But medical science has moved on from such ideas, so we do not use this word to refer to mental illness any more.

5. Moonshine

What better way to finish our list than with a drink? Having said that, we’re not sure how many of you would pick moonshine as your beverage of choice.

If you buy moonshine today, it will probably be from a shop. But the term was first applied to smuggled or illegally distilled liquor, illicit activities that always occurred at night. It may also be related to the word “moonraker,” which is associated with English smugglers for the same reason.

Thank You, Moon

Finally, let us say a brief thank you to the moon. Sure, with modern science we know it’s a big hunk of rock that just sits in the sky, not some god or goddess watching over us. But it has been with us since before humanity had the gall to shape tools from flint, never mind strap ourselves to rockets and blast off into the void to pay it a visit. And we see that influence across human culture, art and – as shown above – language.

As a species, then, we owe the moon a lot. And that’s before we even get on to its role in controlling the tides. So next time you use the word “month” or “menstruation,” spare a thought for our lunar friend.