Where does “чаһы” come from?

чаһы (Yakut) comes from Russian часы́, from Russian час, from Old East Slavic часъ, from Proto-Slavic časъ, from Proto-Balto-Slavic keʔs-, from Proto-Indo-European k(ʷ)eh₁s-.

чаһы (Yakut): clock, watch

Definitions

clock, watch

Ancestry of “чаһы”, step by step

Step	Language	Word	Meaning
1	Russian	часы́	clock, watch
2	Russian	час	hour, o'clock, time, time of day; hours, o'clock;...
3	Old East Slavic	часъ	time; hour; happiness, luck
4	Proto-Slavic	časъ	time
5	Proto-Balto-Slavic	keʔs-	—
6	Proto-Indo-European	k(ʷ)eh₁s-	—

Every word from Proto-Indo-European k(ʷ)eh₁s- →Every word from Proto-Balto-Slavic keʔs- →Every word from Proto-Slavic časъ →