at once

1. 1.

   without delay or hesitation; with no time intervening

   “he answered immediately”

   “found an answer straightaway”

   “an official accused of dishonesty should be suspended forthwith”

   “Come here now!”

   Synonymsimmediatelyinstantlystraightawaystraight offdirectlynowright awayforthwithlike a shot
2. 2.

   simultaneously

   “he took three cookies at a time”

   Synonymsat a timeat one time

Questions about at once

What does at once mean?

at once means "without delay or hesitation; with no time intervening". That is the primary sense; the word has 2 in total, listed in full on this page.

What is another word for at once?

Close synonyms include immediately, instantly, straightaway, straight off, directly. Each sense on this page lists its own synonyms, because a word with several meanings rarely has one substitute that works for all of them.

Is at once a common word?

at once is banded "Common" — everyday vocabulary in speech and writing. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.