'all at once' definitions:
Definition of 'all at once'
From: WordNet
adverb
All at the same time; "Let's say `Yes!' all at once" [syn: all together, all at once]
adverb
Without warning; "all at once, he started shouting" [syn: all of a sudden, all at once]
Synonyms of 'all at once'
From: Moby Thesaurus
- abruptly,
- all together,
- at a blow,
- at a stroke,
- at once,
- at one blow,
- at one jump,
- at one stroke,
- at one swoop,
- at one time,
- bang,
- collectively,
- communally,
- conjointly,
- corporately,
- dash,
- en masse,
- ensemble,
- forthwith,
- hastily,
- impetuously,
- impulsively,
- in a body,
- in a hurry,
- in association,
- in company,
- in conjunction,
- jointly,
- like a flash,
- like a thunderbolt,
- mutually,
- now,
- of a sudden,
- on short notice,
- per saltum,
- plop,
- plump,
- plunk,
- pop,
- precipitantly,
- precipitately,
- precipitously,
- pronto,
- right away,
- right now,
- right off,
- sharp,
- simultaneously,
- slap,
- smack,
- startlingly,
- straightaway,
- straightway,
- subito,
- sudden,
- suddenly,
- surprisingly,
- then and there,
- this minute,
- this very minute,
- together,
- unawares,
- unexpectedly,
- unitedly,
- uno saltu,
- without delay,
- without notice,
- without warning