withered trees and frozen rocks; aloof and unapproachable person
A yojijukugo describing a bleak winter landscape, figuratively used for someone who is cold, stern, and difficult to approach.
He is like a withered tree and frozen rock, and rarely opens up.
枯木寒巌の景色が広がる冬山を一人で歩いた。
I walked alone through the winter mountains, where the scenery of withered trees and frozen rocks stretched out.
冷酷 means 'cruel' or 'cold-hearted', while 枯木寒巌 emphasizes an unapproachable, stern demeanor rather than active cruelty.
A yojijukugo combining 枯木 (withered tree) and 寒巌 (cold/frozen rock), evoking a desolate winter scene. The figurative meaning of an aloof person derives from this imagery.