From the OUP Blog, by Anatoly Liberman

Fart looks like a product of our time, but it has existed since time immemorial. Even the nuances have not been lost: one thing is to break wind loudly (farting); quite a different thing is to do it quietly (the now obscure “fisting”). (This fist has nothing to do with fist “clenched fingers” and consequently isn’t related to fisting, a sexual activity requiring, as we are warned, great caution and a lot of tender experience. This reminds me of the instruction Sergei Prokofiev gave to his First Piano Concerto: “Col pugno,” that is ‘with a fist’.)

Both words for the emission of wind (fart and fist) were current in the Old Germanic languages. Frata and físa (the accent over the vowel designates its length, not stress) turned up even in Old Icelandic mythological poems. According to a popular tale, the great god Thor was duped by a giant and spent a night in a mitten, which he took for a house. He was so frightened, as his adversary put it, that he dared neither sneeze nor “fist.” In another poem, the goddess Freyja, notorious for her amatory escapades, was found in bed with her brother and farted (apparently shocked by the discovery).

The words were as vulgar then as they are today. Yet even grammar proves their antiquity. Some verbs (they are called strong) form their principal parts by changing the root vowel, for instance, write/wrote/written, sing/sang/sung. Others (they are called weak) add a dental suffix (d or t) in the preterit and the past participle, for example, beg/begged/begged, look/looked/looked, wait/waited/waited.

Strong verbs belong to the most ancient part of the Germanic vocabulary. Fart was one of them; however, it occurred in several forms. Modern German has retained farzen (now a weak verb, though furzen is the most common form) and Furz (a noun). In the older period, German also had furzen and ferzan. Engl. fart goes back to ferten, an exact congener of ferzan. Although it was recorded only in the verbal noun ferting, its existence can be taken for granted. I assume that the group er in it changed to ar in the same way in which person yielded its doublet parson and clerk became Clark (in British English, clerk and Clark are homophones).

Icelandic freta and frata were the product of metathesis, that is, the vowel and the consonant r switched places in them. Freta remained a strong verb, but frata became weak. Fortunately, our frat boys seldom if ever take Old Icelandic and are spared the embarrassment. On the other hand, they might enjoy the double entendre.

Although part of the oldest stock, the verb for breaking wind was “popular,” even “low,” and this may have been the reason its shape varied so widely. Compare even such more dignified but “common” names as scrimmage and scrummage, mentioned in the June “gleanings,” part 2, and the names recorded for a wagon or cart: lorry, lurry, rolly, and rully, all meaning “trolley.”

An even more surprising thing is that fart is not only ancient Germanic but Common Indo-European. It has cognates from Lithuanian to Sanskrit and Greek, but naturally they begin with p and have d after r (compare Sanskrit pard-, Russian perdet’ with stress on the second syllable, and so forth) because according to a well-known law, Germanic consonants underwent a shift and that is why Latin pater and duo correspond to Engl. father and two.

The history of fist (to break wind quietly) is similar to that of fart. Vowels in this verb also varied, as evidenced by the Dutch noun veest “fisting”, with ee (pronounced like e in Engl. vest but prolonged!) from ai. Icelandic físa preserved the oldest form, without the suffix t appended to the root. It too has excellent cognates.

Apparently, alongside Indo-European perd-, the near synonymous root pezd- existed (another instance of variation!). It must have been current in Proto-Latin. The sought-for cognate in that language is pedo, with long e (its length is a “compensation” for the loss of z).

The amazing thing is that the cognates are such a perfect match. For example, Russian bzdet’, as well as its Lithuanian congener, are exact glosses of German fisten and Icelandic físa, namely “break wind without making a noise.” Seeing how broad the range of meanings among cognates usually is, one can only wonder at absolute precision in such a word. In Old French, the reflex of ped- was pet-; hence petard.

If perd- and pezd- arose as variants of the same root, fart and fist are ultimately related and sound imitative, even though in the world of onomatopoeia relatedness is a rather vacuous concept. It may seem that perd and pezd do not render the sound of breaking wind.

However, pezd- is rather obviously related to several verbs for whistling and hissing. It appears that everything began with pezd (quiet fisting), which developed into perd, that is, the sound increased in volume (from z to r). At least one eminent language historian set up the ancient root perzd- and allowed the recorded forms to have lost either r or z, but this is a self-serving reconstruction. Such is the tentative history of Indo-European farting, and only one addition is in order here. In Indo-European, many words have variants with and without s- at the beginning. If Latin spiro “blow” (as in Engl. inspire) is one of them (s-piro), it may be allied to the Germanic F-words discussed above.

Those interested in the subject and not only in words may want to read the book by Valerie Allen On Farting: Language and Laughter in the Middle Ages (Palgrave 2007), but should skip the short section on etymology with its erroneous conclusion.

Scatological words are always embarrassing to discuss. But linguists are like doctors: desensitizing makes them indifferent to many things that excite others. In the office they are professionals, and words are just words to them. Other than that, they are normal people.

Read more on the OUP Blog.

Anatoly Liberman is the author of Word Origins…And How We Know Them as well as An Analytic Dictionary of English Etymology: An Introduction. His column on word origins, The Oxford Etymologist, appears on the OUP blog, each Wednesday. Send your etymology question to him care of; he’ll do his best to avoid responding with “origin unknown.”

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