un·sta·ble/ʌn`stebḷ; ʌnˈsteɪbəl/ adj 1 likely to change suddenly and become worse 易变的; 动荡不定的: The political situation is very unstable at the moment. 目前的政治形势相当不稳定。 2 someone who is unstable is likely to suddenly become violent, angry etc, especially because there is something mentally wrong with them 〔人〕反复无常的〔尤因精神问题〕 3 likely to fall over 不稳的,不坚固的: an unstable wall 摇摇欲坠的墙