不絕如縷（不絶如縷）　

◎ 不絕如縷 bùjué-rúlǚ

[almost extinct;very precarious like a thread going to break] 象用一根細(xì)線連著,形容極其危急?，F(xiàn)在也形容聲音細(xì)微而連綿不斷

或者人已經(jīng)轉(zhuǎn)過山頭望不見了,歌聲還余音裊裊,不絕如縷。——《歌聲》