Etymology of the word 'fart' in a handful of PIE languages

[Pythagorean]

"Fart" is one of the best conserved words out there. For a general idea of the modern linguistics view of how the Proto Indo European language evolved into languages today, grok:

There were actually two Proto Indo European words for fart with distinct meanings:
*perd- to fart loudly
*pesd- to fart softly, to break wind

Russian/Slavic:
in Russian, today, fart is пердеть or "perdet" having barely changed at all through the early balto-slavic tribes to the east slavic tribes to modern Russian. Russian also still has a quiet form: бздеть but it seems to have mutated a bit more, through pьzděti in the proto slavic tribes.

English/Germanic:
The Germanic tribes mutated p -> f and d -> t in many words. You can see this by comparing French and English words (as the latin tribes retained the p). In Proto Germanic it's *fertaną, in Old English it becomes feort then eventually fart in modern English.

(notice English also has dropped conjugation, so we aren't adding suffixes to words anymore. In Russia they still do conjugation on every word like we used to in Old English. English and Russian both inherited conjugation from the ancestral proto-indo-european language, but Russia conserved it and English dropped it, using word order to imply object and subject instead).

French/Latin:
The proto-italics evolved *pesd- to *pedzo then pedo in Latin and simply ped in French.

 

[Klystron]

As consonants evolved with different languages, vowel sounds also shifted, often locally.

For example, my friends from Nova Scotia speak comparatively identical North American English as I. Yet, the open mouthed pronunciation of vowels in such words as "out" and "about" mark a distinct local Canadian dialect ("oot" and "ah-boot").

The Op's subject word "fart" undergoes vowel shifts between languages such as English and German and within local variants of the latter. The German director Wolfgang Petersen plays with this shift in the German language director's cut version of the WWII submarine flick Das Boot.

Bored petty officers joke about farts (Furts) in the close quarters submariners share, with one film critic claiming to identify the purported home origin of the characters based on their pronunciations. Oddly, some Americans read the German title as 'das boot' while the German pronunciation sounds much closer to the English translation 'boat'.

 

[Pythagorean]

A common vowel shift I notice between other Germanic languages and English is ei vs. o
home <-> heim
stone <-> stein
bone <-> bein
ghost <-> geist

 

[Klystron]

notice English also has dropped conjugation, so we aren't adding suffixes to words anymore.

Dropped most declensions, also, Latin to English. In some sense English adopted Roman Latin with greatly simplified construction. Certainly, studying (modern) Latin helps build English vocabulary, if not grammar.

Areas that Ancient Rome closely colonized such as Gaul (Francia), Iberia (Yspania) and, of course, Italia adhered to Latin regular construction so much more than languages of loosley occupied lands such as Britannia and Hibernia with adopted vocabulary but irregular usage. This begs the question how much German retains Latin given the spotty occupation attempts of tribal lands.

 

[Pythagorean]

Dropped most declensions, also, Latin to English. In some sense English adopted Roman Latin with greatly simplified construction. Certainly, studying (modern) Latin helps build English vocabulary, if not grammar.

Areas that Ancient Rome closely colonized such as Gaul (Francia), Iberia (Yspania) and, of course, Italia adhered to Latin regular construction so much more than languages of loosley occupied lands such as Britannia and Hibernia with adopted vocabulary but irregular usage. This begs the question how much German retains Latin given the spotty occupation attempts of tribal lands.

English borrows heavily from Latin but I wonder if it didn't break the language barrier until around when conversion happened and churches came to England (bringing Latin scholarship with them). Old English and Old Norse were relatively mutually intelligible when they were both spoken before conversion - they had both split from northern Germanic tribes relatively recently and had similar inflection and shared many root words - their runes were fairly similar. After conversion, and Latinization of Germanic languages, Old Norse split into Icelandic, Norwegian, Danish (and a couple others). Norwegian, Danish, Scots, and English (northern Germanic offspring languages) all sort of transitioned to systems that depend on word order instead of conjugation. English has already lost masculine/feminine case, Norwegian and Danish are in the process of losing it.