Definitions:

1. simultaneously adverb
   • At once, he picked up the book from the table and started reading.
2. simultaneously adverb
   • *The chief's quick actions saved the day at once.
3. simultaneously adverb
   • *The doctor advised her to stop smoking at once.
4. simultaneously adverb
   • *She was ready at once when we called her.
5. simultaneously adverb
   • *As soon as the traffic light turned green, he started the car at once.
6. simultaneously adverb
   • *At once, he ran to the aid of the victim.
7. simultaneously adverb
   • *He saw the accident and at once called the police.
8. simultaneously adverb
   • *At once, she understood what I meant.
9. simultaneously adverb
   • *The teacher asked the students to be quiet at once.
10. simultaneously adverb
    • *He was very angry and at once told her to leave.
11. simultaneously adverb
    • *The boss asked him to come to his office at once.
12. simultaneously adverb
    • *At once, he realized his mistake.
13. simultaneously adverb
    • *She started crying at once when she heard the news.
14. simultaneously adverb
    • *At once, he knew that something was wrong.
15. simultaneously adverb
    • *The fire alarm rang and at once everyone left the building.
16. simultaneously adverb
    • *The baby started crying at once when he was put down.
17. simultaneously adverb
    • *At once, he jumped into the water to save the drowning man.
18. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
19. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
20. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
21. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
22. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
23. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
24. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
25. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
26. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
27. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
28. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
29. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
30. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
31. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
32. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
33. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.
34. without delay or hesitation adverb
    • At once, he picked up the book from the table and started reading.

Synonyms:

• at a time
• at one time
• in the same breath
• instantly