Where does “шахмати́ст” come from?

шахмати́ст (Russian) comes from Russian ша́хматы, from Persian شاه مات — checkmate.

Ancestry of “шахмати́ст”, step by step

Step	Language	Word	Meaning
1	Russian	ша́хматы	—
2	Persian	شاه مات	checkmate

шахмати́ст — Etymology, Origin & Word History | Etymology Explorer