枯

dried up

surname Gu

ancient / old / paleo-

(bound form) tree / (bound form) wood / unresponsive; numb; wooden

withered / dried up

withered

dead leaf / withered leaf

to rack one's brains (for apt wording etc) (idiom)

dull and lonely

dead tree

lit. the spring comes upon a withered tree (idiom) / fig. to get a new lease on life / to be revived / (of a difficult situation) to suddenly improve

withered and rotten

Agent Orange (herbicide)

dried bones in burial mound (idiom); dead and buried

Bakuninism, a 19th century socialist theory