Definition of "Unstable" :

adjective: subject to change; variable

"Everything was unstable following the coup."

adjective: affording no ease or reassurance

adjective: highly or violently reactive

"Sensitive and highly unstable compounds."

adjective: disposed to psychological variability

"His rather unstable religious convictions."

adjective: suffering from severe mental illness

adjective: lacking stability or fixity or firmness

"Unstable political conditions."