Where does “oğulcuq” come from?

oğulcuq (Azerbaijani) comes from Turkish -cık, from Ottoman Turkish ـجك, from Proto-Turkic *-čük — Forms denominal dimunitive nouns.

Ancestry of “oğulcuq”, step by step

StepLanguageWordMeaning
1Turkish-cıkdiminutive suffix
2Ottoman TurkishـجكDiminutive suffix after front vowels
3Proto-Turkic*-čükForms denominal dimunitive nouns
Every word from Proto-Turkic *-čük →Every word from Turkish -cık →Every word from Ottoman Turkish ـجك →