instantaneously
In no time
Instantaneously means happening in an instant, without any perceptible delay: The message arrived instantaneously.
It emphasizes immediacy more than instantly, suggesting no measurable time passes between cause and effect.
Scientists might note that nothing truly happens instantaneously—light takes time to travel—but in ordinary use, the word describes anything that feels immediate: She instantaneously recognized the song.
Happening without delay
- simultaneousHappening at same time
- real-timeOccurring without processing delay
- split-secondFraction of a moment
- momentBrief period of time
blink · flash · nanosecond · microsecond · millisecond · heartbeat · snap · jiffy
Moving with haste
- swiftMoving with speed
- fastSpeedy, or skip eating
- quickMoving with speed
- speedyCharacterized by quickness
lightning · meteoric · breakneck · express · fleeting · momentary · transient · ephemeral
Sharp and unexpected
- suddenOccurring without prior notice
- unexpectedNot anticipated beforehand
- shockViolent sudden disturbance
- joltAbrupt forceful shake
startling · unforeseen · unanticipated · bolt · thunderbolt · jarring · snap · whiplash
immediate
Happening without delay
- simultaneousHappening at same time
- real-timeOccurring without processing delay
- split-secondFraction of a moment
moment · blink · flash · nanosecond · microsecond · millisecond · heartbeat · snap · jiffy · twinkling
rapid
Moving with haste
speedy · lightning · meteoric · breakneck · express · fleeting · momentary · transient · ephemeral · velocity
abrupt
Sharp and unexpected
- suddenOccurring without prior notice
- unexpectedNot anticipated beforehand
- shockViolent sudden disturbance
jolt · startling · unforeseen · unanticipated · bolt · thunderbolt · jarring · snap · whiplash · blindsiding
instantaneouslyslowly
At reduced speed
gradually · incrementally · leisurely · sluggishly · unhurriedly
instantaneouslyeventually
At a later time
later · finally · afterwards · subsequently · in time
instantaneouslygradually
In slow stages
incrementally · progressively · step by step · bit by bit · little by little
- instantaneous reactionResponse occurring without delay