Meaning of UNSTABLE in English

UNSTABLE

/ ʌnˈsteɪbl; NAmE / adjective

1.

likely to change suddenly

SYN volatile :

The political situation remains highly unstable.

2.

if people are unstable , their behaviour and emotions change often and suddenly because their minds are upset

➡ note at mentally ill

3.

likely to move or fall

4.

( technical ) ( of a substance ) not staying in the same chemical or atomic state :

chemically unstable

OPP stable

—see also instability

Oxford Advanced Learner's English Dictionary.      Оксфордский английский словарь для изучающик язык на продвинутом уровне.