IPA: /ˈskɛr.kɪst/
KK: /ˈskɛr.kəst/
This word describes something that is in very short supply or not easily available.
Water is the scarcest resource in the desert.
Comparative: scarcer
Superlative: scarcest
Scarcest is formed from "scarce" (from Old French *escarc*, meaning insufficient or limited) and the superlative suffix "-est" (meaning most). The word "scarcest" means the most limited or least available.
Think of something that is 'limited' ('scarce') and when it is at its highest degree of limitation, it becomes the 'scarcest'.