- simultaneously: The children were running, screaming, and throwing things all at once.
- suddenly: All at once the rain came down.
- at the same time; simultaneously: Don't all speak at once.
- immediately; promptly: Tell him to come at once!
British Dictionary definitions for all at once
- suddenly or without warning
Word Origin for once
Idioms and Phrases with all at once (1 of 2)
all at once
All at the same time, as in We can't get inside all at once, so please wait your turn. [Late 1300s]
Suddenly, unexpectedly, as in All at once the sky darkened. For a synonym, see all of a sudden.
Idioms and Phrases with all at once (2 of 2)
In addition to the idioms beginning with once
- once and for all
- once bitten, twice shy
- once in a blue moon
- once in a lifetime
- once in a while
- once over lightly
- once upon a time
- all at once
- at once
- every now and then (once in a while)
- give someone the once-over