causing distress or worry or anxiety; "distressing (or disturbing) news"; "lived in heroic if something distressful isolation"; "a disturbing amount of crime"; "a revelation that was most perturbing"; "a new and troubling thought"; "in a particularly worrisome predicament"; "a worrying situation"; "a worrying time"
not appropriate in application; defective; "an infelicitous remark"; "infelicitous phrasing"; "the infelicitous typesetting was due to illegible copy"
marked by or producing unhappiness; "infelicitous circumstances"; "unhappy caravans, straggling afoot through swamps and canebrakes"- American Guide Series
having momentous consequences; of decisive importance; "that fateful meeting of the U.N. when...it declared war on North Korea"- Saturday Rev; "the fatal day of the election finally arrived"