Where does “Қостанай” come from?

Қостанай (Kazakh) comes from Kazakh қос, from Proto-Turkic *koš — pair, double.

Ancestry of “Қостанай”, step by step

Қостанай traces back through two separate lines of ancestry.

via Kazakh қос

StepLanguageWordMeaning
1Kazakhқосpair set of two
2Proto-Turkic*košpair, double

via Kazakh танай

StepLanguageWordMeaning
1Kazakhтанай
Every word from Proto-Turkic *košEvery word from Kazakh қос
Қостанай — Etymology, Origin & Word History | Etymology Explorer