Where does “इसतक” come from?

इसतक (Hindi) comes from Hindi इस, from Prakrit 𑀅𑀲𑁆𑀲, from Sanskrit अश्व, from Proto-Indo-Aryan Háśwas, from Proto-Indo-Iranian Háćwas, from Proto-Indo-European h₁éḱwos, from Proto-Indo-European h₁oh₁ḱu- — swift.

Ancestry of “इसतक”, step by step

इसतक traces back through two separate lines of ancestry.

via Hindi इस

StepLanguageWordMeaning
1Hindiइसthis - oblique case only, see below for direct;...
2Prakrit𑀅𑀲𑁆𑀲of this
3Sanskritअश्वhorse, stallion; knight; the number "seven"
4Proto-Indo-AryanHáśwas—
5Proto-Indo-IranianHáćwashorse
6Proto-Indo-Europeanh₁éḱwosstallion, horse
7Proto-Indo-Europeanh₁oh₁ḱu-swift

via Hindi तक

StepLanguageWordMeaning
1Hindiतकtill
2Sauraseni Prakrit𑀢𑀯𑀓𑁆𑀓—
3Sanskritतावत्कbought for so much
4Sanskrit-कdoer, maker
5Proto-Indo-Aryan*-kas—
Every word from Proto-Indo-European h₁oh₁ḱu- →Every word from Proto-Indo-European h₁éḱwos →Every word from Proto-Indo-Iranian Háćwas →