IPA: /ˈskɛr.sər/
KK: /ˈskɛr.sɚ/
This word describes something that is not easy to find or is available in limited amounts.
Water is scarcer in desert regions than in areas with abundant rainfall.
Scarcer → It is formed from "scarce" (from Old French *escarc*, meaning thin or scant) and the comparative suffix "-er" (meaning more). The word "scarcer" means more thinly distributed or less available than something else.
Think of something that is 'thin' or 'scant' ('scarce') and remember that 'scarcer' means it is even less available.