• 老朽ろうきゅう

  infirmity (due to old age), decrepitude, senility, senescence, superannuation

• 不朽ふきゅう

  everlasting, immortal, eternal, enduring, undying, imperishable

• 朽廃きゅうはい

  decay, dilapidation

• 朽壊きゅうかい

  rotting and crumbling

• 若朽じゃっきゅう

  being young yet unambitious, being young but lacking spirit

• 腐朽ふきゅう

  decay, deterioration, rot

• 朽ち葉くちば

  decayed leaves

• 朽ちるくちる

  to rot, to decay

• 朽ち木くちき

  decayed tree, rotted tree, decayed wood, rotten wood

• 黄朽葉きくちば

  reddish-yellow (colour), russet

• 腐朽菌ふきゅうきん

  wood-decay fungus, xylophagous fungus

• 青朽葉あおくちば

  bluish russet

• 老朽化ろうきゅうか

  deterioration, becoming decrepit, becoming worn out

• 朽ち葉色くちばいろ

  russet, tawny, yellow-brown

• 乾燥腐朽かんそうふきゅう

  dry rot

• 永垂不朽えいすいふきゅう

  one's fame or achievements being passed down eternally

• 不朽不滅ふきゅうふめつ

  everlasting, eternal, immortal, imperishable, undying

• 朽ち果てるくちはてる

  to rot away, to crumble to dust, to decay completely, to fall to ruins, to rust away

• 不朽の名作ふきゅうのめいさく

  timeless masterpiece, immortal work

• 木材腐朽菌もくざいふきゅうきん

  wood-decay fungus, xylophagous fungus

• 蛇に噛まれて朽ち縄に怖じるへびにかまれてくちなわにおじる

  once bitten twice shy, to become over cautious from a bad experience, to be bitten by a snake and thus fear a rotten rope (which resembles a snake)