What is another word for more frost-bound?
Pronunciation: [mˈɔː fɹˈɒstbˈa͡ʊnd] (IPA) 
The phrase "more frost-bound" refers to a situation or place that is even colder than it already is. Synonyms for this term include "bitterly cold," "icy," "chilly," "frosty," and "arctic." Each of these words emphasizes the extreme coldness of the situation, whether it refers to the weather, an environment, or a state of mind. "Bitterly cold" evokes the idea of a sharp, biting cold that is almost painful to experience. "Icy" brings to mind frozen landscapes and the danger of slipping on ice. "Chilly" suggests a milder cold that one might feel on a brisk autumn day. "Frosty" brings to mind the breath misting in the air on a cold winter day. "Arctic" is a more extreme synonym, suggesting a frigid, inhospitable environment.
