Where does “zásaditý” come from?

zásaditý (Czech) comes from Czech zásada, from Czech zasadit, from Old Czech zasaditi, from Proto-Slavic *zasaditi.

zásaditý (Czech): basic, alkaline

Definitions

Step	Language	Word	Meaning
1	Czech	zásada	alkali, base; principle, rule, precept
2	Czech	zasadit	—
3	Old Czech	zasaditi	—
4	Proto-Slavic	*zasaditi	—

zásaditý — Etymology, Origin & Word History | Etymology Explorer