Reconstruction:Proto-Slavic/trьbuxъ

• *terbuxъ[1]

Unclear. Main propositions conjure origin:

• Vasmer, Trubačev: From *trь- (“tri-”) +‎ *buхъ (“swelling”), perhaps from Proto-Indo-European *bʰew- (“to swell, to bulge”). Possibly akin to Proto-Slavic *buxyrь (“gut, intestine”) (whence Slovak buchyr (“gut”)), Proto-Germanic *būkaz (“belly”). Prefix, while not entirely clear, likely reflects *trь- (“tri-”), maybe in reference to the compartmentation of some herbivores' digestive tract (cattle, camels, and other ruminants).
• Snoj: From *terbъ (“something stretched or torn up”) +‎ *-uxъ. Possibly akin to Latin strebula (“flesh around the haunch”).

*trьbűxъ m[1]

1. stomach, paunch (typically of animals)

   Synonyms: *břuxo, *puzo

2. bowels, intestines, guts

• *trěbuxъ, *tribuxъ (with widening of prefixial *-ь- > *-i-/*-ě-)
• *trьbuxa f

• *trьbušiti (“to gut, to butcher”)
• *trьbušęstъ, *trьbušatъ (“having large stomach, guts”)

• *buxati (“to blow away, to strike, to swell”)
  • *buxyrь, (possibly) *baxurь (“gut, intestine”)
  • *buxъta (“nugger”)
• *buza (“cheek, uproar”)
• *terbiti (“to cleanse, to tear through”)

• East Slavic:
  • Old East Slavic: трибꙋхъ (tribuxŭ)
    • Belarusian: трыбу́х (trybúx) (dialectal)
    • Russian: трибу́х (tribúx) (dialectal)
    • Ukrainian: трибу́х (trybúx), трибуха́ f (trybuxá, “animal guts”) (dialectal)
  • Belarusian: трэбу́х (trebúx)
  • Russian: требуха́ (trebuxá, “guts”)
  • Ukrainian: тельбу́х (telʹbúx, “intestine”)
• South Slavic:
  • Old Church Slavonic: трьбоухъ (trĭbuxŭ)
  • Bulgarian: търбу́х (tǎrbúh)
  • Macedonian: трбув (trbuv) (dialectal)
  • Serbo-Croatian:

    Cyrillic script: тр̀бух

    Latin script: tr̀buh

  • Slovene: trẹ́buh
• West Slavic:
  • Czech: terbuch m, třebucha f
  • Polish: trybuch, terbuch
  • Slovak: terbuch
  • Sorbian:
    • Lower Sorbian: tarbuch

• Vasmer, Max (1964–1973) “требуха”, in Oleg Trubachyov, transl., Этимологический словарь русского языка [Etymological Dictionary of the Russian Language] (in Russian), Moscow: Progress
• Trubachyov, Oleg, editor (1976), “*buxyrъ”, in Этимологический словарь славянских языков [Etymological dictionary of Slavic languages] (in Russian), numbers 3 (*bratrьcь – *cьrky), Moscow: Nauka, page 82