all of a sudden adv 1: without warning; "all at once, he started shouting" [syn: {all of a sudden}, {all at once}] 2: happening unexpectedly; "suddenly she felt a sharp pain in her side" [syn: {suddenly}, {all of a sudden}, {of a sudden}]
Sudden \Sud"den\, n. An unexpected occurrence; a surprise. [1913 Webster] {All of a sudden}, {On a sudden}, {Of a sudden}, sooner than was expected; without the usual preparation; suddenly. [1913 Webster] How art thou lost! how on a sudden lost! --Milton. [1913 Webster] He withdrew his opposition all of a sudden. --Thackeray. [1913 Webster]
29 Moby Thesaurus words for "all of a sudden": abruptly, bang, dash, hastily, impetuously, impulsively, like a flash, like a thunderbolt, of a sudden, on short notice, plop, plump, plunk, pop, precipitantly, precipitately, precipitously, sharp, short, slap, smack, startlingly, sudden, suddenly, surprisingly, unawares, unexpectedly, without notice, without warning