at once   (TTS Sound)

The adv at once has 2 senses

• immediately, instantly, straightaway, straight off, directly, now, right away, at once, forthwith, like a shot -- (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!")


• at a time, at once, at one time -- (simultaneously; "he took three cookies at a time")