Reconstruction:Proto-Slavic/-ačь

• Morphologically possibly from reinterpreting of some deverbal agent nouns (e.g. *kovačь ← *kovati +‎ *-čь : *kovъ +‎ *-ačь). Synchronically it is an independent suffix.
• Semantically it's close to denominal suffix *-atъ. But in this case form **-aťь is expected, though compare *porťa : *porkъ.

*-ačь m

1. Denominal, forming nouns denoting a carrier of a property.

   *kolo (“wheel”) → *kolačь (“cake”)

   *bogъ (“wealth, fortune”) → *bogačь (“a wealthy man”) (compare *bogatъ (“wealthy”))

   *borda (“beard”) → *bordačь (“a bearded man”) (compare *bordatъ (“bearded”))

   *golva (“head”) → *golvačь (“one having a big head”) (compare *golvatъ)

   *rogъ (“horn”) → *rogačь (“horned animal”) (compare *rogatъ (“horned”))

• *-atъ
• *-akъ

• East Slavic:
  • Old East Slavic: -ачь (-ačĭ)
    • Old Ruthenian: -ачъ (-ač)
      • Belarusian: -а́ч (-áč)
      • Ukrainian: -а́ч (-áč)
    • Russian: -а́ч (-áč)
  • Old Novgorodian: -аць (-aćĭ)
• South Slavic:
  • Bulgarian: -ач (-ač) (rare)
  • Macedonian: -ач (-ač) (rare)
  • Serbo-Croatian: (rare?)

    Cyrillic script: -а̄ч

    Latin script: -ȃč

  • Slovene: -áč
• West Slavic:
  • Old Czech: -áč
    • Czech: -áč, -ač
  • Old Polish: -acz
    • Polish: -acz
    • Silesian: -ŏcz
  • Polabian: -ăc
  • Pomeranian:
    • Kashubian: -ôcz
    • Slovincian: -ócz
  • Slovak: -áč
  • Sorbian:
    • Upper Sorbian: -ač
    • Lower Sorbian: -ac

• Šekli, Matej (2012) “Besedotvorni pomeni samostalniških izpeljank v praslovanščini”, in Philological Studies‎^[1] (in Slovene), volume 10, number 1, Skopje, Perm, Ljubljana, Zagreb, pages 115–32
• Sławski, Franciszek, editor (1974), “*-ačь”, in Słownik prasłowiański [Proto-Slavic Dictionary] (in Polish), volume 1 (a – bьzděti), Wrocław: Ossolineum, page 102