Thesaurus

acting, activated, adjustable, aflicker, agitated, amok, amuck, apprehensive, around the bend, arrhythmic, astatic, balmy, barmy, bats, batty, berserk, bonkers, brainsick, buggy, certifiable, certified, changeable, changeful, checkered, convulsive, coseismal, coseismic, crackbrained, cracked, crackers, crank, cranky, crazed, crazy, daft, demented, demoniac, demoniacal, deranged, discouraged, distortable, distracted, disturbed, dotty, ephemeral, episodic, erratic, evanescent, exchangeable, excited, explosive, false, faltering, fey, fickle, flickering, fluctuating, fluid, fly-by-night, fruity, fugacious, half-crazed, haywire, hebephrenic, idiotic, impermanent, improvised, inconstant, indecisive, infirm, insane, interim, irrational, irregular, irresolute, jerking, jerky, jittering, jury-rigged, kaleidoscopic, kaleidoscopical, kookie, kooky, labile, loco, loony, loopy, lunatic, mad, makeshift, maniac, maniacal, manic-depressive, maniclike, mentally ill, mercurial, mobile, moonstruck, non compos mentis, nuts, nutty, of unsound mind, open-ended, oxidizable, palpitant, palpitating, paranoid, passing, possessed, precarious, pro tem, pro tempore, psychopathic, psychopathologic, psychopathological, psychotic, quavering, quick-change, quick-drying, quicksilver, raving, raving mad, reactive, reversible, rickety, rocky, round the bend, schizophrenic, screw-loose, screwy, seismal, seismic, shaky, shifting, shifty, shivering, short-lived, shuddering, sick, spasmodic, spastic, temporal, temporary, tender, tense, terminable, thermolabile, tippy, tipsy, top-heavy, tottering, tottery, touched, transient, transitory, trembling, tremulous, unbalanced, uncomfortable, uneasy, uneven, unfaithful, unhinged, unquiet, unreasonable, unsound, unstable, unsteady, untrue, vacillant, vacillating, variable, volatile, volcanic, wacky, wavering, weak-kneed, whacky, wild, wobbling, wobbly, wonky, working, worried

unstable is a ADJ.