What is the etymology of frog? I'm referring to the elaborate braid fastenings often found on 18th and 19th century military costumes, not the amphibian.

enter image description hereenter image description here

Wikipedia tells me

Frogs and frogging became an important decorative feature on military uniforms from the 17th–19th centuries. This was particularly evident for prestigious regiments, especially cavalry or hussars, and gave rise to the German term for frogging in general, 'Husarentressen'. These dolman jackets were tight-fitting and dominated by extensive frogging, often in luxurious materials such as metallic cording or brocades.

No mention of who invented that type of button or where it originated from, and not a word on its etymology. Etymonline was a little more helpful:

frog (n.2) type of fastening for clothing, 1719, originally a belt loop for carrying a weapon, of unknown origin; perhaps from Portuguese froco, from Latin floccus "flock of wool."

The OED mentions when the ‘buttons’ frogs first appeared in print.

1746 Berkeley Let. Wks. “Laces, frogs, cokades..are so many..obstacles to a soldier's exerting his strength.”

and offers this second example

1770 W. Richardson Anecd. Russian Emp. 25 “In a light blue frock with silver frogs.”

The term for the amphibian—frog—is derived from Old English frogga, so it's been around a long time. Why call a hand sewn button a frog then? Was it military slang? Did the Portuguese invent this type of closure? Was this an English variation on the Chinese knot?

I don't speak Portuguese, so I asked Google translator to lend me a hand. It suggested chenille a type of yarn or fabric, but it's also the French word for caterpillar, the yarn is said to resemble the caterpillar's soft fur. Those frogs look neither soft or fuzzy to me. However, frock, which originally meant a man's overcoat and a type of smock for both men and women, is a loanword derived from Old French froc and Middle French frocq.

Returning to the uniforms, we can see there are a fair number of frogs adorning the military jacket. By the mid 18c, the braidings had become gold and covered the entire front; was this only embellishment or did the metal buttons and thick knots ostensibly offer protection against sword cuts?

enter image description here
Captain F Farquharson of Eastbury, Dorset, 7th Hussars, 1836.

Which led me to wonder what a large group of frogs (amphibians and fasteners) would be called. There are three venery terms for a group of frogs

  1. army of frogs 2. knot of frogs 3. colony of frogs

The question is, did the venery terms precede the name of the fasteners, in which case I think we may have a plausible answer to my first question, or were these collective nouns coined in the 19th century?


  1. Why are these fasteners called frogs?
  2. Were they always called frogs, the term sounds like a witticism.
  3. Was the term frog (fastener) a loanword from French, Portuguese or Latin?
  • 3
    Great. Another DBDV, a plague on this site. The print versions of the OED are no help, hiding behind "obscure." Sorry.
    – deadrat
    Commented Oct 4, 2015 at 17:19
  • 2
    The full OED has 4 (apparently etymologically unrelated) nouns frog. My first thought that your "fastening" sense was the same as the depression on the top surface of some bricks, but OED lists that one under the "animal" version. For the etymology of your one, they say Origin unknown. N.E.D. (1898) suggests as etymon Portuguese froco ( < classical Latin floccus flock n.2), which it comments ‘has much the same sense’, but no use denoting a type of fastening is recorded in dictionaries. So really, I expect anything posted here is probably going to be just idle speculation. Commented Oct 4, 2015 at 17:20
  • 1
    My speculation is that it really is an allusion to the amphibian. OED say of their earliest (1635) citation frog buttons are often covered in silk or similar material. I reckon that's highly reminiscent of a real frog's skin, which is not only "slippy" to the touch like silk, but could probably also be easily slid/pushed sideways over the underlying solid button, just like with a real frog (imagine trying to slide a human being's skin over his skeleton in relative proportion to what you could do with a frog! :) Commented Oct 4, 2015 at 17:29
  • 2
    (Besides, that would put me in the position of "formally" claiming I know more about such matters than OED, which is simply not tenable! ;) Commented Oct 4, 2015 at 17:35
  • 3
    @FumbleFingers It's not a matter of opinion any more than the scholarship that goes into the OED's own etymologies are "matters of opinion". There are recognized and productive ways of establishing etymologies. What it is, however, is a question which sets an extremely high bar for an answer. I've noticed most etymology questions where askers have already consulted the OED and Etymonline and found no satisfaction simply go unanswered. I've only ever seen one answer which contained fresh, comprehensive and credible new research for an etymology, and that one was deleted by its owner :(
    – Dan Bron
    Commented Oct 4, 2015 at 17:38

6 Answers 6


The origin of the term frog in relation to the braid on military uniforms (and almost uniquely cavalry uniforms) might come from the old term for frock. The OED has:

Frock 2. An upper garment worn chiefly by men... 1375. Barbour Bruce x. 375 With blak froggis all helit thai The Armouris at thai on thame had. c 1425 Wyntoun Cron. viii. xxxviii. 57 Ilkane a gud Burdowne in hand, And royd Frogis on þare Armyng. c 1460 Towneley Myst. (Surtees) 241, I wold be fayn of this frog [Christ's coat] myght it fall vnto me. 1500–20 Dunbar Poems li. 3 To giff a doublett he is als doure, As it war off ane futt syd frog

A 14th Century 'frock' or 'frog'. Note the belt and cord carrying gear. The term frog-loop and frog-belt have been used to describe these items up to the 19th Century (see below) and even today a frog-loop is still a term for a retainer for a tool in a tradesman's belt.

enter image description here

There are also references in the Dictionary of the Scots Language:

Frog, Froig, n.1 [ME. frog, frogge (15th c.), of uncertain origin.] A frock; a cloak or coat. Barb. x. 375. With blak froggis all helyt thai The armouris at thai on thame had; Wynt. viii. 5702. [They had] royd frogis on thare armyng, To covyre thame for persaywyng; Crying of Play 39. Five thousand ellis ȝeid in his frog Of hieland pladdis of haire; Dunb. li. 3. To giff a doublett he is als doure, As it war off ane futt syd frog; Doug. vi. v. 132. In hevy wayt frog stad and chargyt soyr; 1550–1 Treas. Acc. IX. 467. Spanȝe freis … to be ane froig to my Lady;

So what we might be looking at is frog(frock)-button, and frog(frock)-belt, as below:

1719 De Foe Crusoe ii. iv. (1840) II. 68 He drew a hatchet out of a frog-belt. 1827 Hone Every-day Bk. II. 190 A coat with frog-buttons. 1867 Smyth Sailor's Word-bk., Frog-belt, a baldrick.

Curiously (and perhaps destructively to this argument) Defoe 1719 also has:

1719 De Foe Crusoe i. xv, A belt with a frog hanging to it, such as..we wear hangers in.

Tailoring of simple jackets, frocks or 'frogs' only became usual from the 1500's onwards. Prior to that they were held in shape with belts, cords, lacing and over the shoulder straps which served the dual function of carrying tools and possessions on hooks and loops, and in bags hung from them. Pockets are a relatively late invention in clothing. (See: http://www.theinnerbailey.com/baileybasics-sets-townsman-1.jpg)

My suggestion (tending towards an answer) is that this early fashion of belting, lacing and buttoning was contemporary with the use of the ME word 'frog' for jacket, and the the technical expressions for items associated with them such as frog-button, frog-belt, frog-loop and frogging were all developed during that time. As fashion evolved in the 1500-1600 period and clothes were more tailored to the shape of the body and pockets came into use, not only did the term 'frog' evolve into 'frock', but those belts and cords became less important for shaping the material and for carrying items. Frog as a word for a frock evolved, but the use of frog in association with those accoutrements became fossilized.

To see how these fossilized terms for buttoning and braiding (frog-buttons, frogging) came to be associated with a military fashion of the early 1700's (in England) we need to look at Eastern Europe in the late 1400's.

Frogging (as we call it) is most closely, and most extravagantly, associated with lightly armoured mounted troops known as Hussars or Dragoons. This link to an image from c.1550 clearly shows the horizontal braid on a mounted Hungarian soldier's uniform:

enter image description here

Such troops, and their dress styles, evolved in Eastern Europe before spreading to Western Europe in the late 1600's. None of the languages or cultures (including that of the Ottoman Empire) appear to have contributed the word 'frog' or 'frogging' along the way.

The actual fashion which became quickly extravagant and an actual impediment to military action (1746 Berkeley Let. Wks. 1871 IV. 306 Laces, frogs, cockades..are so many..obstacles to a soldier's exerting his strength.) may have originated in loops in the jacket to hold additional weapons such as daggers and short swords, or in the lacing used to tighten loose plates of armour or a baggy cloth jacket around the body.

When the new style reached England in the mid 1700's there was no current word to describe the braiding (that had become increasingly ornate as it travelled west across Europe). It was recognized, however, as similar to the ornamentation formerly (and no longer) used on the item of clothing once known as a frog. The names for that ornamentation (including 'frogging') had never evolved because the items had been largely disused for about a hundred years, but were revived in their original form to describe the ornamentation on this new (to English eyes) military fashion.

This speculative essay into the evolution of the use of the word 'frog', and the suggestion that it's original association with the article of clothing, and the accoutrements to that clothing went down different paths, and that the word for the accoutrements was frozen for some one or two hundred years while the word for the clothing evolved, and how the frozen word was revived to describe a new fashion element, also explains how we arrived at DeFoes (otherwise improbable) description of a 'frock with frog-buttons'. Essentially he is saying, 'a frock with frock-buttons', but the language available to him has him say otherwise.

  • 2
    The term frock in relation to military 'gear' is well established, again the OED Frock of mail: a defensive garment, armour. Cf. coat of mail. 1671 Milton Samson 133 Samson..Made arms ridiculous, useless the..frock of mail Adamantean proof. 1835 Browning Paracelsus iii. 715, I have addressed a frock of heavy mail, Yet may not join the troop of sacred knights... But I will chase an illustration as you suggest. And also acknowledge that @JEL (as I now discover) got to 'frock' before me.
    – John Mack
    Commented Oct 7, 2015 at 12:53
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    A very descriptive account of 'frock coats' in the British Military: britishempire.co.uk/forces/armyuniforms/britishartillery/….
    – John Mack
    Commented Oct 7, 2015 at 13:02
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    JEL may have suggested that frog was connected to frock but he also said he couldn't prove it, whereas you.... :)
    – Mari-Lou A
    Commented Oct 8, 2015 at 6:15
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    @Josh61 I suggest the term applied to uniform decorations (froggings) and button closures called frogs essentially comes from the archaic or dialect English words for similar (but more utilitarian) items on an archaic garment known as a frog. Why 'frog-belt', 'frog-loop' and frog-button did not evolve linguistically into 'frock-belt', 'frock-loop' and 'frock-button' while the word for the underlying garment did evolve is explained if these accoutrements became less necessary (as pockets evolved) and more unfashionable over time. A working garment 'frog' became a high status garment 'frock'.
    – John Mack
    Commented Oct 8, 2015 at 12:25
  • 1
    @Josh61 ... further to the above ... When the very ornate style of cavalry frock arrived via France and Austria with a great many buttons and loops English speakers reached back in time to retrieve long disused terms to describe them, not having anything so ornate in their fashion lexicon or words to describe them in the current English lexicon. The functional purpose of the loops in both the original English 'frog' and the original Eastern European cavalry uniform are explained in the Answer. I'd call this answer 'speculative, but plausible'. A fashion expert might tell us more.
    – John Mack
    Commented Oct 8, 2015 at 12:37

An extract from The Life and Extraordinary History of the Chevalier John Taylor, etc. The biography was written by his son in 1761, and was printed in Dublin, Ireland.

The story begins when the Norwich-born John Taylor is 19 years old in 1722. He is trained as an eye surgeon in St. Thomas's hospital in London, and during his career as an oculist he worked in England, Holland, Ireland and France; on page 78, the doctor flees to Portugal. During the three years he lives there, the ‘Chevalier’ becomes incredibly wealthy “… he restored to Sight the Viceroy of Brazil; for which Feat he got, to use his own Words, a Hat full of Gold, ...” Later, he escapes back to England where his father lives.

Having lately landed from Portugal, he writes to his father, who sends him immediately two Suits of Cloaths of blue Damsk lined with black Silk, and embossed with Frogs of the same colour. The Air and Cut of these Cloaths expressed something foreign, which the Mob, in their great Wisdom, were pleased to call Frenchified.


THUS equipped, the young Chevalier travels to the Borough-Fair; where he seems an human Exotic in the Eyes of that polite Assembly. They soon saw the Ridiculousness of his Dress, and judged the Singularity of it to be a public Crime, which, by the Law of Nations, the Populace have ever presumed to punish.
A handsome genteel young Man, with a modest and inoffensive Deportment, is made the Butt of Insolence, Brutality and Abuse, in the most merciless and savage Manner, because he wore Frogs upon his coat, his Hat under his Arm, and his Sword by his Side.
The prescribed Criminal, with more Frogs on his Coat than he set out with, escapes to the Water-Side half frighted to Death; takes Boat, and in a Day or two recovers his Reason, and his Cloathing in some Degree.

The above extract appears to confirm that frog ‘buttons’ were used to adorn men's coats, hats, and belts, as described in @John Mack's answer.

Frog waistcoat buttons before OED's 1746 ...

The earliest match I found for these ornamental loops and buttons is dated 1735 from The Account of the Behaviour, Confessions, and Dying Words, of the Malfactors, who were executed at Kennington-Common (source)

enter image description here

…when he went into the Tavern he was dressed in a lightcolour'd grey Coat and Breeches, and a white Waistcoat with Frogs; but that whilst this Deponent was getting Assistance to apprehend him he had chang'd his Cloaths, to a brown Coat and Buck-skin Breeches…

and after 1746

In The Fortunate Country Maid Vol II, 1748

“… Is he not a tall young Man with black Eyes, and wears a Plaister or large Patch on his Forehead, his Hair curled, and had on when he came a light brown Surtout with gold Frogs?”. You are right, (replied the Stranger) ‘it is certainly he; I am very lucky in meeting you! And, tell me, pray is he here still?

and in the same year: A catalogue of English heads: or, An account of about two thousand prints

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  1. Edward Lord Hinchingbrooke. Cap, Collar unbutton'd frogs, dated 1701
    (The print shows the eight-year-old Viscount, the eldest son of the 3rd Earl of sandwich)
  2. The Right Honourable Stephen Poyntz, Esq; ... Wig, Neckcloth, Frogs to his Coat
  • What an interesting Q&A. Your questions are a boon to the site. :) Commented Oct 12, 2015 at 18:18

The image you posted shows a Prussian hussar uniform.

The braid called a frog, is described this way on Wikipedia:

A frog fastener (also Chinese frog) is an ornamental braiding, consisting of a button and a loop, for fastening the front of a garment. The purpose of frog fasteners is to provide a decorative closure for a garment; frog fasteners are usual to garments of Asian design, such as a shirt or coat with a mandarin collar, which features frog fasteners at the shoulder and down the front of the garment. In the design of a garment, frogging is the use of braided, frog fasteners is a detail of the overall design of the garment.

In French, it's called "Brandebourg", from the German city of Brandebourg.

Frogs and frogging became an important decorative feature on military uniforms from the 17th–19th centuries. This was particularly evident for prestigious regiments, especially cavalry or hussars, and gave rise to the German term for frogging in general, 'Husarentressen'.

Why are these fasteners called frogs?

The etymology is given here:


type of fastening for clothing, 1719, originally a belt loop for carrying a weapon, of unknown origin; perhaps from Portuguese froco, from Latin floccus "tuft of wool," a word of unknown origin.

There's good chance it comes either from Portuguese froco (translated by "chenille" in English, borrowed to the French word meaning "caterpillar) or fromp French froc (frock).

I think it's more logical that it could comes from French "froc", because of the history of military wars.


Were they always called frogs, the term sounds like a witticism.

No, it's not derogatory at all, it's the opposite, it's a prestigious ornement.
No link with the slang associated with the amphibian, describing first the Dutch, then the French, as it's a borrowed word that changed, and wasn't directly meaning "a frog".

Was the term frog (fastener) a loanword from French, Portuguese or Latin?

As I showed in the link, nobody can be sure of the etymology.


Still only a "perhaps" ... The Oxford American Dictionary has the amphibian as frog1 and the fastener as frog2. For the "Origin" of frog2 it says


  • 1
    My French dictionary indicates that "fourchette" (fork) is also used for the "frog" of a horse's hoof.
    – GEdgar
    Commented Oct 6, 2015 at 17:56
  • I think that the Italian suggestion refers to "a grooved metal plate for guiding the wheels of a railway vehicle at an intersection", but Frog for a decorative fastening does not seem to be the same word and its origin is unknown.oxforddictionaries.com/it/definizione/inglese/…
    – user66974
    Commented Oct 7, 2015 at 10:26
  • I believe that the dictionary's explanation fits for the frog that is in a horse's hoof because it is V shaped. A forked road is also similar. I'm going to downvote this answer because it's inaccurate.
    – Mari-Lou A
    Commented Oct 10, 2015 at 11:00
  • @GEdgar I've never seen "fourchette" to describe a "brandebourg". Could you paste the text?
    – Quidam
    Commented Oct 19, 2019 at 13:26

I notice that bowed stringed instruments, have on their bows, "frogs" that hold the hair firmly to the bow stick. Being familiar with "frogs" on clothing, especially those in a Chinese style, it seemed to me a small leap that the French bow-makers of the 19th Century adopted the word from clothing to bows. My research on musical instrument sites claim there to be no agreement on the origin of the word "frog" except that it became routine during the flourishing of French bow making masters. That is shares the notion of "closure" with clothing is all I have been able to share with my young string students who invariably ask "why?"


I agree with the idea posted above by Ginny A. I have obsessed over this Bow Frog thing and had found nothing at all until I understood that this "Frog" is a mechanical fastener/clamp. Indeed, I have found a wide variety of clamping devices and tool components called frogs or frog clamps. Some of these resemble the shape of a crouching frog, as does the bow frog. So, I believe the term "Frog" in this context is a metaphor. :-)

*Pictured are:

1) Stanley NO.4 frog

2) Frog Finger splints

Finger clampsBench planer Frog

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