undependable 

英汉解释

adj. 靠不住的，不可靠的；不可信赖的

同义词

a. unreliable

反义词

a.   dependable，reliable

参考例句

1. He often described himself as a somewhat undependable machine .
他常常把自己比做一架不大可靠的机器。
2. He says projects designed to increase interpersonal trust can have a major effect in poor countries with undependable legal systems.
他说，增加人与人之间的信任的项目对于司法体系不可靠的贫穷国家起到非常重要的作用。
3. But Internet service in Uganda proved slow and undependable. So Question Box teamed up with a local technology company to store information on a local server.
但是乌干达的网络服务非常缓慢而且不稳定，所以问题格子与当地技术公司联系，将信息储存在地方服务器上。

英英解释

adj.
  1. not worthy of reliance or trust
  2. liable to be erroneous or misleading

网络释义

undependable
靠不住;