Synonyms and related words :
adrift, afloat, alternating, amorphous, capricious, changeable, changeful, desultory, deviable, dizzy, eccentric, erratic, fickle, fitful, flickering, flighty, flitting, fluctuating, freakish, giddy, impetuous, impulsive, inconsistent, inconstant, indecisive, infirm, irregular, irresolute, irresponsible, mazy, mercurial, moody, rambling, restless, roving, scatterbrained, shapeless, shifting, shifty, shuffling, spasmodic, spineless, unaccountable, uncertain, uncontrolled, undependable, undisciplined, unfixed, unpredictable, unreliable, unrestrained, unsettled, unstable, unstable as water, unstaid, unsteadfast, unsteady, vacillating, vagrant, variable, vicissitudinary, vicissitudinous, volatile, wandering, wanton, wavering, wavery, wavy, wayward, whimsical, wishy-washy