unstable

adjective

1. 1

   subject to change; variable

   a fluid situation fraught with uncertainty

   everything was unstable following the coup

2. 2

   affording no ease or reassurance

   a precarious truce

3. 3

   highly or violently reactive

   sensitive and highly unstable compounds

4. 4

   disposed to psychological variability

   his rather unstable religious convictions

5. 5

   suffering from severe mental illness

   of unsound mind

6. 6

   lacking stability or fixity or firmness

   unstable political conditions

   the tower proved to be unstable in the high wind