Etymology

Considering that the word for foot in French is pied, I guessed before doing my research that foot was going to be another example of an English word with Germanic roots instead of Latin ones.

As it turns out, though it does have Germanic roots, the Germanic and Latin roots both come from the same Proto-Indo-European (PIE) root, ped-.

So how does ped become foot? First, ped became fot in Old English. Let’s play around with some possibilities as to how.

Voiced vs. Unvoiced Consonants

Make a t sound. Pay attention to how your mouth moves.

Now make a d sound. You’ll notice that your mouth moves in the exact same way.

So what makes them sound different from each other?

Place your hand on your throat while you make both sounds again.

Feel the vibrations while you make the d sound? That’s because you use your vocal cords, which creates the distinction.

You now know the difference between voiced and unvoiced consonants.

Other pairs of consonants that are only different thanks to vibrations include b/p, v/f, and z/s.

With that in mind, the d at the end of ped changing to a t at the end of fot is a fairly seemless change.

Grimm’s Law

The p to an f is beyond my limited linguistic knowledge. After an hour of research, I still don’t quite understand the exact sequence of changes, though apparently it’s not a unique situation. According to Grimm’s Law, there was a general shift from the p sound in PIE to the f sound in English.

My humble musings could imagine that a possible pathway from p to f could have been:

p > b (unvoiced consonant to voiced counterpart)
b > v (This part of the theory is very not technical, but I could see this change in terms of Spanish where the b and v sounds for Anglophones can be hard to tell apart. How many times have you heard a non-native English speaker say “bery good” instead of “very good”?)
v > f (voiced to unvoiced counterpart)

Wait, did I just do algebra with sounds?

Laziness

Finally, it’s not that hard for vowels to change. It happens all the time, especially to a more easily pronounced vowel. I don’t have proof, but my guess is (based on paying attention to how my mouth moves when I make each sound) that the vowel e uses more muscles and is thus more difficult to pronounce, even if minutely, than the vowel o.

All in all, it makes sense how ped could have become fot and subsequently foot.

Quirks

Once I started looking into the etymology of foot, I rabbit-holed very quickly into other aspects of the word.

I-Mutation

As an example of how easily vowels change over time, let’s look at another intriguing part of the word foot: its plural form.

The English language is full of infuriating irregularities and plural forms that aren’t marked with an s is one of its most infamous (#TwoFish). So why does foot become feet?

As part of the natural human tendency to make language easier, the main vowel in a word sometimes changes in anticipation of the next vowel in a suffix. So, in the case of i-mutation, if your brain knows it needs to pronounce an o and then an i, it will pronounce the o more similarly to an i because it is easier to pronounce the same thing twice.

In the context of foot, this applies because the plural form in ancient West Germanic, instead of the suffix -s like it is today, was the suffix –iz. This means that the plural of foot was footiz. Over hundreds of years of making that oo sound more like the i, the word eventually becomes feetiz. From there, the meaning of the word is already understood in the first four letters and the ancient plural suffix is dropped, leaving us with feet.

Cultural Context

The whole reason I thought to look into the etymology of foot has nothing to do with the anatomical meaning and everything to do with the form of measurement.

As an American, getting asked how tall you are in France isn’t a simple question to answer. Though, since I’ve been asked several times, I can now share the 5’8” translates to 1.73 meters.

What really caught my attention though was the French referring to feet as pieds. Now, as I mentioned in the beginning of this article, that is the direct translation for the things at the end of our legs that we walk on, but – since I had never associated the French word with a form of measurement – it seemed like such a silly word for it.

I then asked some friends if it is common for French people to be familiar with the Imperial system (which, in case you don’t know, is what the non-metric system is called). The response I mostly get is that they probably know it exists, but they only learn about it if it’s relevant to either their job (of the scientific variety) or a hobby (such as athletics involving distances like miles).

During this conversation, I was asked what the English word was for pousse. A little surprised at the seeming non sequitur (aka random question), I responded with the translation: thumb. Through context though, I quickly figured out though that I was wrong. I mean, it is the word for thumb, but I figured out that it has a second meaning.

Apparently, in the same way that foot is a body part and a form of measurement in both French and English, so is a thumb in French. If you think about the size of the average thumb, you’ll likely guess that this is the word the French use for inch.

When I responded with surprise at this, I got questions like, why a body part for one and not the other?

Twelve thumbs in a foot. What’s weird here: the French language or the Imperial system?

Happy middle of the week, Nerds! Thanks for suggestions for next week’s words; they’re in the works! Feel free to leave more suggestions in the comments below or on Insta.

References

Online Etymology Dictionary: Foot
https://www.etymonline.com/word/foot

Grimm’s Law
https://www.britannica.com/topic/Grimms-law

Online Etymology Dictionary: I-Mutation
https://www.etymonline.com/columns/post/imutate