Synonyms for unstable

modified

1. Having a high center of gravity

   unsteady, wavering, unbalanced, giddy, wobbly, wiggly, weaving, shifty, precarious, top-heavy, teetering, shifting, uncertain, rattletrap, beetling, jutting, lightly balanced.

   Antonyms firm*, steady, solid.

2. Easily disturbed

   variable, changeable, inconstant, giddy, capricious, fluctuating, shifty, volatile, rootless, dizzy, unpredictable, uncertain, sensitive, oversensitive, thin-skinned, timid, delicate.

3. Subject to fission

   fissionable, fissiparous, fractionable; see weak 2. See syn. study at inconstant.