(a.) Not resolute; not decided or determined; wavering; given to doubt or irresolution.

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