Where does “плавательный” come from?

плавательный (Russian) comes from Russian пла́вать, from Proto-Slavic plavati, from Proto-Slavic plàviti, from Proto-Slavic -vati.

плавательный (Russian): swimming

Definitions

Step	Language	Word	Meaning
1	Russian	пла́вать	to swim
2	Proto-Slavic	plavati	to swim; to float; to sail
3	Proto-Slavic	plàviti	—
4	Proto-Slavic	-vati	—

плавательный — Etymology, Origin & Word History | Etymology Explorer