If you ask an English speaker to define the word frog, most would presumably think immediately of the tailless amphibian of the family Ranidae. We’ve had that word in English since at least 1000 CE, when it appears in descriptions of the Bible’s second plague of Egypt. And in fact, although frog would seem to be a pretty simple, straightforward word with a simple, straightforward definition, the English language actually has a veritable plague of different frog words.
I can begin with a number of phrases that clearly derive from this same, amphibious word.
frog in the throat - our current definition, a slight hoarseness, presumably because it makes you sound like you’re croaking, dates back only to about 1900. However, frog was used of a variety of diseases of the mouth and throat all the way back to around 1650.
leap-frog - (c.1600) a game obviously named for its suggestion of leaping like a frog
frog-march - (c. 1870) Our current definition of hustling someone forward with their arms pinned behind them may not seem to have much connection with our amphibian, but the word first meant crawling, and then carrying someone face-down by their four limbs, both of which look more froggish.
frogman - (c. 1945) a scuba diver, who, with wet suit, flippers, and oxygen tank, can swim like a frog, and looks rather like one, too
Frog - This derogatory slang for a French person derives from the stereotype of frogs being a noteworthy element of French cuisine. It appeared around 1778 when the French were siding with the Americans against Britain, and it took off during the Napoleonic Wars. But back in the 1650s, before turning against the French, the slang was applied to Dutch people because of the marshiness of the Netherlands.
It’s relatively easy to see the frog-connection in those words, and they are only a sampling of words clearly derived from the amphibian. There are plenty of other animals (like frogfish and frogmouth), plants (like frog's-bit and frog spit), etc, named after frogs. But that’s only the beginning of frog in English.
frog - an ornamental fastening for a coat, consisting of a spindle-shaped or knotted toggle or button that passes through a loop; plus the related definition of a loop on a belt from which a scabbard or holster may be carried. This frog is of unknown origin, but may be derived from Portuguese froco, from Latin floccus “tuft of wool, or cord” (c. 1710)
frog - an elastic, horny organ in the middle of the sole of a horse’s foot, also of doubtful origin, but perhaps from French fourchette (c. 1610)
frog - a grooved piece of iron placed at the junction of the rails where one track crosses another, possibly derived from its resemblance to the frog of a horse’s hoof (c. 1850)
frog - the part of the bow of a stringed instrument by which the bow is held. The etymology of this one has a plague of theories: perhaps from Latin floccus (like the toggle) because it’s where the horsehair is attached; or perhaps because the shape was thought to resemble the bottom of a horse’s foot (like the railroad switch); or perhaps from the vice used in the crafting of the bow, called a frock (though where that name came from I don’t know); or perhaps from a part of a plane used in bowmaking called a frog (again, no explanation of that one); and perhaps from German frosch meaning “frog,” which was a word for a riser block that spaces items as the frog of a bow holds the hair away from the stick… Yeah, let’s just admit that no one has a clue.
frog - in a moldboard plow, the frame or standard to which soil-wearing parts are attached. I can’t find any etymology or date on this definition, but I’ll throw out a wild off-the-cuff speculation that perhaps it could relate to Old High German pfluog, “plow.”
And then what about just a few more that might be related to the amphibian…
frog - recessed area in the side of a brick. According to the only place I found a derivation given, the word comes from the part of a traditional brick mold that released the clay. This was called kikker in Dutch, which means frog. English speakers translated the word when they borrowed it. Presumably the kikker was called so in the first place because it kicks the clay out of the box with a jump.
frog - a small spiked or perforated object placed in the bottom of a vessel to hold flower stems in position in an arrangement. This may possibly have begun as a slang term in the 1920s and 30s because they sit in water, but there is no evidence to support the theory one way or the other.
frog - In fiber artist slang, to pull knitting off the needles and unravel it. This is by far our most recent frog, with the first attested use c. 1996. The etymology usually given is that if you pull out all your needlework you “rip it, rip it,” which of course sounds like a frog. This may or may not be a folk etymology, but given the recent informal invention of the term, it’s entirely possible.
I called this list a plague of frogs, but of course all these words are not a disaster at all, but instead a party! I first became tickled by the idea that there were multiple unrelated meanings of the word frog when I began to play the cello at age ten, and around that same time came upon the word frog to refer to the decorative knotted fastenings. I remember feeling quite delighted by this quirk of the English language. I hope it delights you, too.
[Pictures: Dancing Frogs, wood block print by Tokuriki Tomichiro, 1950s (Image from Ukiyo-e.org);
Leap Frog Boys, woodcut by Leona Pierce, 1951 (Image from The Old Print Shop);
Magyar Hussar with frogs on his jacket, his belt, and his horse, wood block print after a drawing by Jost Amman, c. 1550 (Image from Wikimedia Commons);
Bullfrog, collagraph by AEGN, 2012.]