n. 死河, 死水潭

Billabong \Bil"la*bong`\, n. [Native name.]
In Australia, a blind channel leading out from a river; --
sometimes called an {anabranch}. This is the sense of the
word as used in the Public Works Department; but the term has
also been locally applied to mere back-waters forming
stagnant pools and to certain water channels arising from a
source.
[Webster 1913 Suppl.]