dead of winter 冬之死；隆冬；严冬

【例句】
You're travelling in the dead of winter?
你要在冬天最冷的时候旅行？

It was the dead of winter, and the ground was covered in thick frost, and icicles were hanging from the trees.
隆冬时节，积霜遍地，冰柱垂枝。