unsteady

convulsive, sudden, violent

broken, disconnected, fragmentary, interrupted

aimless, arbitrary, desultory, haphazard, hit-and-miss, hit-or-miss, odd, random, scattered, slapdash, stray

capricious, changeful, changing, flickery, fluctuating, fluid, inconstant, mercurial, mutable, temperamental, uncertain, unpredictable, unsettled, unstable, varying, wavering

changeable, fickle, variable, volatile

aimless, arbitrary, desultory, erratic, haphazard, hit-or-miss, irregular, random, scattered, slapdash, stray

ambivalent, hesitating, shaky, shilly-shally, shilly-shallying, vacillating, wavering

dicey, undependable, unreliable, untrustworthy

adaptable, mobile, protean, versatile

rocky, shaky, tippy, tipsy, wavery, wobbly (also wabbly)

infirm, insecure, precarious, unsound

doddering, doddery, jiggling, jiggly, rickety, teetering, tottering, tottery

askew, awry, cockeyed, lopsided, off-kilter, uneven

capricious, changeable, changeful, choppy, fickle, fluid, inconsistent, inconstant, mercurial, mutable, uncertain, unsettled, variable, volatile