Synonyms and related words :
alarmingness, appallingness, awfulness, creepiness, direness, disconcertingness, dismayingness, disquietingness, dreadfulness, eeriness, fearfulness, fearsomeness, frighteningness, frightfulness, ghastliness, ghoulishness, grimness, grisliness, gruesomeness, hideousness, horribleness, spookiness, startlingness, terribleness, uncanniness, weirdness