early 13c., "apt to move," from un- (1) "not" + stable (adj.). Similar formation in Middle High German unstabel. Meaning "liable to fall" is recorded from c. 1300; sense of "fickle" is attested from late 13c. An Old English word for this was feallendlic, which might have become *fally.
实用例句
1. Their politics consisted of unstable power-plays between rival groups.
他们的政治活动包括竞争团体间反复多变的打压行动。
来自柯林斯例句
2. The situation is unstable and potentially dangerous.
情况不稳定，可能有危险。
来自柯林斯例句
3. She was physically delicate and psy-chologically unstable.
她身体孱弱，心理上也不够稳定。
来自柯林斯例句
4. Both clay and sandstone are unstable rock formations.
黏土和砂岩都是不牢固的岩石构造。
来自柯林斯例句
5. Europe had become infinitely more unstable and fragmented.
