Reconstruction:Proto-Slavic/-ъkъ

Nominal suffix, formed by rebracketing of *-kъ, typically appended to ancient u-stems. Can also be attached to o-stems to form derivatives of the specified object/property. Compare Proto-Iranian *-akah and Sanskrit -अक (-aka) formed in the same way.

*-ъkъ m

1. Forms diminutives from old u-stem nouns

   *listъ (“leaf”) → *listъkъ (“leaflet, a small leaf”)

   *synъ (“son”) → *synъkъ (“boy, little son”)

   *bebrъ (“beaver”) → *bebrъkъ (“small beaver”)

   *medъ (“honey”) → *medъkъ (“honey product”)

2. Deadjectival, denoting a carrier of the specified property (rare)

   *pętъ (“fifth”) → *pętъkъ (“Friday”)

   *četvьrtъ (“fourth”) → *četvьrtъkъ (“Thursday”)

   *bělъ (“white”) → *bělъkъ (“albumen”)

   *žьltъ (“yellow”) → *žьltъkъ (“yolk”)

   *okrǫžьnъ (“circumferential”) → *krǫžьkъ (“circle, shape with circular form”)

3. Structural formant, without a base noun to synchronically derive from

   *pěsъkъ (“sand”)

4. Deverbal from the past participle in *-tъ, forms resultant nouns of the specified action

   *dobyti (“to extract”) → *dobytъ → *dobytъkъ (“stock”)

   *dati (“to give”) → *datъ → *datъkъ (“yield”)

   *zaperti (“to expire”) → *zapьrtъ → *zapъrtъkъ (“addle egg”)

   *začęti (“to conceive”) → *začętъ → *začętъkъ (“embryo, germ”)

5. Deverbal, forms abstract nouns of the specified action

   *pominǫti (“to pass”) → *pominъkъ (“livelihood, means to survive”)

   *do (“to, nearby”) + *jьměti (“to have”) → *nedojьmъkъ (“poverty, lack of income”)

6. Deverbal, forms an instance of the specified action

   *kyvati (“to knock, to hew”) → *kyvъkъ (“nod”)

   *telťì (“to shove, to pound”) → *tьlčьkъ (“push, impulse”)

   *mazati (“to anoint, to spread oil/paint”) → *mazъkъ (“dab, smear”)

   *glъtati (“to swallow”) → *glъtъkъ (“gulp”)

7. Deverbal, forms tool or agent nouns for the specified action: -er

   Synonyms: *-ьcь, *-slo

   *strěľati (“to knock, to hew”) → *strělъkъ (“shooter”)

   *skrebti (“to scrape”) → *skrebъkъ (“scraper”)

   *gǫděti (“to buzz, to honk”) → *gǫdъkъ (“horn, buzzer”)

   *pьlzti (“to craw”) → dial. *pьlžьkъ (“slug”)

8. From propositions, forms an instance of the specified action

   *perdъ (“in front”) → *perdъkъ (“ancestor”)

   *po +‎ *tomь (“later on, over there”) → *potomъkъ (“descendant”)

Adjectival suffix with analogical origin as the nominal suffix. Related to Proto-Germanic *-ugaz (when appended to u-stems) and Proto-Germanic *-agaz (to o-stems). In rare case, both the original u-stem form (reanalyzed as an o-stem) and the extended *-ъkъ are attested: e.g. Old Church Slavonic крѣпъ (krěpŭ) : крѣпъкъ (krěpŭkŭ).

*-ъkъ

1. From nouns or adverbs, forms adjectives with pertaining meaning: -y

   *kortъ (“piece, bit”) → *kortъkъ (“short”)

   *nizъ (“down, below”) → *nizъkъ (“nether, low”)

   *slizъ (“slime”) → *slizъkъ (“slippery”)

   *goře(stь) (“sorrow, woe, tribulation”) → *gorьkъ (“bitter”)

   *tęžе(stь) (“weight”) → *tęžьkъ (“heavy”)

2. Deverbial from the past participle, forms adjectives which approximate the meaning of the participle: -ly (rare)

   *plyti (“to float”) → *plytъ (“sunk”) → *plytъkъ (“shallow”)

   *pry(g)ti (“to spring, to jump”) → *prytъ (“sprung”) → *prytъkъ (“agile, nimble”)

   *viti (“to curve, to wind”) → *vitъ (“curved”) → *vitъkъ (“curvу, twisty”)

   *biti (“to beat, to fight”) → *bitъ (“beaten”) → *bitъkъ (“feisty, military”)

3. (Extension) From former u-stem adjective (some of them surviving as re-analyzed o-stems), forms their doublets

   *gladъ → *gladъkъ (“smooth, plain”)

   *dьrzъ → *dьrzъkъ (“daring, bald”)

   *krěpъ → *krěpъkъ (“solid, firm”)

   *krěxъ → *krěxъkъ (“soft, mild”)

   **lьgъ → *lьgъkъ (“light”)

   **mělъ → *mělъkъ (“small, finely ground”)

   **tьnъ → *tьnъkъ (“thin”)

• *-ьkъ (when attached to yu-stems or spread from the ancient comparative in *-jьš-)

• 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
• Halla-aho, Jussi (2006), Problems of Proto-Slavic Historical Nominal Morphology: On the Basis of Old Church Slavic (Slavica Helsingiensia; 26), Helsinki: University of Helsinki, page 100