Mirror comes comes Old French mireor (“reflecting glass”), which sprang from earlier French miradoir (exact translation lost) mirer (“look at”) and Latin mirare, miror, and mirari (“to wonder at, admire”). Certainly mirer is the most direct ancestor here; it also gave birth to admire. But let's take it a step further and look at miror, which takes the gentlemanly mirer and proclaims him anemic. Mirer may admire, but miror? To astonish, to marvel at, to be amazed.
For comparison, window springs from the Old Norse for “wind eye”; bowl comes from proto-Germanic “a round vessel”; we get desk from medieval Latin’s version of “table to write on”; table itself is from Latin’s tabula, a board or plank; dresser is from...you get the picture. Terms for other common furnishings and items stem from utility or purpose. So either mirror is the exception because of its extraordinary powers—or it’s in the same boat as the prosaic desk, and those old French folk knew that we can’t help but be astonished and amazed by our own reflection.
Actually, those old French folk could have just taken the perfectly good Latin word that already existed for mirror: speculum. (Imagine the comedic potential had that happened.) The Italians did just that (specchio), as did the Spanish, Portuguese, and even the Germans (espejo, espelho, and Spiegel, respectively). Speculum also has no-nonsense, utilitarian credentials, springing from specere, or “to look at,” with none of this “astonishment” business coming into play. So why didn’t the French just go with speculum?
Some posit that the Egyptians beat the Romans to France, bringing along mirrors—and their word for them, roughly mau-her—before speculum-waving Romans had a chance to introduce mirrors to the country that would later become known for manufacturing them. That’s one possibility, certainly.
But I prefer to think that France was being a tad more intentional than that. It’s a country that mothered such mirror minds as King Louie XIV and Marie Antoinette (not to mention Jacques Lacan with his mirror stage, and Simone de Beauvoir with her keen eye toward us self-admiring women); its citizens, to the American mind, embody some concepts we associate with mirror-gazing. We American lay-deez adore our French women, not only because we see them as beautiful—plenty of countries are famed for their beautiful women—but because they appear to both blatantly spend time, energy, and money on their appearance, and also appear utterly nonchalant, as though their reputed grace is theirs by birthright. But don’t take the French study of mirrors on my word alone:
Perhaps I haven’t been too far off in referring to the mirror as a divination tool. Historically, alternate uses of mirror include “a crystal used in magic”; indeed, there’s an entire practice of divination via mirrors, catoptromancy (and if anyone knows a practicing catoptromantic, let me know, stat). And, of course, there’s always the verb form of mirror: to mimic, to imitate. We didn’t actually use it to mean to reflect until the 19th century, when Keats put it to use in “Lamia”: He answer’d, bending to her open eyes / Where he was mirror’d small in paradise. In other words, the first time we used mirror to mean reflect, there was not an object, but a human’s eyes, doing the reflecting.
Which, truly, makes sense—especially for those of us who have lopped off those “eyes” by averting our gaze from the mirror. But it also might make sense etymologically: One middle form of mirror is old French miradoir, which, as I mentioned earlier, has been lost. Nobody knows exactly what miradoir means. But in this scholarly debate about the full origin of mirror, a linguist broke down the word into verb forms, “Latin agentive suffixes,” etc., and determined that there’s a good chance that miradoir means not just a thing you look at, but a thing that looks back at you.