all of a sudden

Also found in: Thesaurus, Acronyms, Idioms, Wikipedia.


1. Happening without warning; unforeseen: a sudden storm.
2. Happening or done without delay; hasty or immediate: a sudden decision.
3. Characterized by sharp change in elevation; precipitous: a sudden drop in the ocean floor.
all of a sudden
Very quickly and unexpectedly; suddenly.

[Middle English sodain, from Old French, from Vulgar Latin *subitānus, from Latin subitāneus, from subitus, from past participle of subīre, to approach stealthily : sub-, secretly; see sub- + īre, to go; see ei- in Indo-European roots.]

sud′den·ly adv.
sud′den·ness n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

all of a sudden

- Is the grammatically correct version; do not say "all of the sudden."
See also related terms for sudden.
Farlex Trivia Dictionary. © 2012 Farlex, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adv.1.all of a sudden - without warningall of a sudden - without warning; "all at once, he started shouting"
2.all of a sudden - happening unexpectedlyall of a sudden - happening unexpectedly; "suddenly she felt a sharp pain in her side"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
allt í einu


(ˈsadn) adjective
happening etc quickly and unexpectedly. a sudden attack; His decision to get married is rather sudden!; a sudden bend in the road.
ˈsuddenness noun
ˈsuddenly adverb
He suddenly woke up; Suddenly she realized that the stranger had a gun.
all of a sudden
suddenly or unexpectedly. All of a sudden the lights went out.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.
References in classic literature ?
All of a sudden she was arrested in the middle of a fine paragraph by Mac, who sat bolt upright, brought both feet down with a thump, and said, in a rough, excited tone
Full browser ?