IPA: /ˈtʃɪliɪst/
KK: /ˈtʃɪliɪst/
The most cold or cool in temperature.
Today is the chilliest day of the year, so make sure to wear a warm coat.
Comparative: chillier
Superlative: chilliest
Chilliest → It is formed from "chilly" (from Old English "ciele", meaning cold) and the suffix "-est" (meaning the most). The word "chilliest" means the most cold or the coldest in temperature.
Think of 'chilly' meaning cold, and remember that 'chilliest' refers to the most cold.