IPA: //ˈbeɪsɪst//
KK: /ˈbeɪsɪst/
The lowest or most immoral part of something; lacking in moral principles or values.
His actions were considered the basest of all, showing no regard for others.
Basest → It is formed from "base" (from Old French *base*, meaning foundation or bottom) and "-est" (a superlative suffix indicating the highest degree). The word "basest" means the lowest or most despicable in moral quality or status.
Think of 'base' as the foundation or bottom, and remember that 'basest' refers to the lowest moral quality.