Synonyms and related words :
adrift, afloat, agnostic, alternating, ambiguous, ambitendent, ambivalent, amorphous, at loose ends, bland, capricious, chancy, changeable, changeful, changing, desultory, deviable, dicey, dizzy, double-minded, doubting, dubious, eccentric, equivocal, erratic, faltering, fast and loose, fence-sitting, fence-straddling, fickle, fitful, flickering, flighty, flitting, fluctuating, freakish, giddy, halfhearted, halting, hesitant, hesitating, impetuous, impulsive, incalculable, inconsistent, inconstant, indecisive, indemonstrable, infirm, infirm of purpose, infirm of will, insipid, irregular, irresolved, irresponsible, mazy, mercurial, milk-and-water, milky, moody, mugwumpian, mugwumpish, mushy, mutable, neutral, of two minds, polysemous, rambling, restless, roving, scatterbrained, shapeless, shifting, shifty, shilly-shallying, shuffling, skeptical, spasmodic, spineless, tasteless, tentative, touch-and-go, unaccountable, uncertain, unconfirmable, uncontrolled, unconvinced, undecided, undependable, undetermined, undisciplined, undivinable, unfixed, unforeseeable, unpersuaded, unpredictable, unprovable, unreliable, unresolved, unrestrained, unsettled, unstable, unstable as water, unstaid, unsteadfast, unsteady, unsure, unverifiable, vacillating, vacillatory, vagrant, vapid, variable, vicissitudinary, vicissitudinous, volatile, wandering, wanton, watery, wavering, wavery, wavy, wayward, whimsical, wishy-washy, wobbly