unstable
adjective
1. lacking stability or fixity or firmness
- unstable political conditions
- the tower proved to be unstable in the high wind
- an unstable world economy
Similar word(s): inconstant, impermanent, temporary, coseismal, coseismic, crank, cranky, tender, tippy, explosive, volatile, rickety, shaky, wobbly, wonky, rocky, seismal, seismic, tipsy, tottering, volcanic, unsteady
2. highly or violently reactive
- sensitive and highly unstable compounds
Similar word(s): reactive
3. affording no ease or reassurance
Similar word(s): uneasy, precarious
4. suffering from severe mental illness
Similar word(s): insane, unsound
5. disposed to psychological variability
- his rather unstable religious convictions
Similar word(s): irresolute
6. subject to change; variable
- everything was unstable following the coup
Similar word(s): changeable, changeful, fluid