Hyperborean and Sub-zero

Hyperborean noun - (Greek mythology) one of a people that the ancient Greeks believed lived in a warm and sunny land north of the source of the north wind.

Sub-zero and Hyperborean are semantically related. In some cases you can use "Sub-zero" instead an adjective "Hyperborean".

Hyperborean and sub-zero are semantically related. Sometimes you can use "Hyperborean" instead an adjective phrase "Sub-zero".