Frostier

adjective

1. Cold, chilly.

   "I'd like a frosty milkshake."

2. Having frost on it.

   "The frosty pumpkin is the sign of the end of the growing season, soon the greenery will wither and harvest end for the year."

3. Having an aloof or inhospitable manner.

   "After the divorce, she was civil but frosty to her ex."