枯木死灰 こぼくしかい Meanings Expression, Noun withered trees and cold ash (figuratively: someone who is detached and free of desires) (figuratively: someone who has no vitality) Kanji 枯 wither. Read as コ. 木 tree. Read as ボク. 死 die 灰 ash. Read as カイ. Word lists Yojijukugo (四字熟語) Jinuma: Japanese Dictionary · Word lists