IPA: /ˈkriːpiər/
KK: /ˈkripɪər/
More frightening or unsettling than something else.
The old house looked even creepier at night.
Creepier → It is formed from "creep" (from Old English "creopan", meaning to move slowly or stealthily) and the comparative suffix "-ier" (indicating a higher degree). The word "creepier" means more creepy or causing a greater feeling of unease or fear.
Think of someone moving 'slowly' ('creep') in a way that makes you feel uneasy, and the '-ier' shows that it's even more unsettling.