欲 ㄩ ˋ yù 壑 ㄏㄜ ˋ hè 难 ㄋㄢ ˊ nán 填 ㄊㄧㄢ ˊ tián 慾 ㄩ ˋ yù 壑 ㄏㄜ ˋ hè 難 ㄋㄢ ˊ nán 填 ㄊㄧㄢ ˊ tián bottomless pit of desire (idiom); insatiable greed carnal cravings are never satisfied and are a main obstruction on the path to enlightenment