a.

1. 不稳定的；动荡的；易变的
   Conditions in the coastal towns were unsettled after the hurricane.

   飓风过后沿海城镇的形势颇不稳定。

2. 未定居的，无居民的
   A large part of the southwestern United States is unsettled desert.

   美国西南部的大部分是无人居住的沙漠。

3. 未解决的；不定的；怀疑的
   The argument remains unsettled.

   这项争议仍未解决。

4. 未付清的，未清算的

adj.

1. lacking stability; changeable or liable to change.
   ▸agitated; uneasy.
2. not yet resolved.
   ▸(of a bill) not yet paid.
3. (of an area) having no settlers or inhabitants.