noun

the quality or state of being hesitant.

Jackson took advantage of some hesitancy in the defence to rifle in a shot

uncertainty,hesitation,hesitance,unsureness,doubt,doubtfulness,dubiousness,irresolution,irresoluteness,indecision,indecisiveness,equivocation,vacillation,wavering,scepticism,nervousness,second thoughts,dithering,stalling,shilly-shallying,temporizing,temporization,pausing,delay,hanging back,waiting,havering,humming and hawing,swithering,dilly-dallying,blowing hot and cold,dubiety,incertitude,cunctation,reluctance,unwillingness,disinclination,unease,uneasiness,ambivalence,demurral,compunction,misgivings,qualms,scruples,reservations