instantaneous
adjective
in·stan·ta·neous ˌin(t)-stən-ˈtā-nē-əs 
-nyəs
1
: done, occurring, or acting without any perceptible duration of time
death was instantaneous
2
: done without any delay being purposely introduced
took instantaneous corrective action
3
: occurring or present at a particular instant
instantaneous velocity
instantaneity
ˌin-ˌstan-tə-ˈnē-ə-tē
noun ˌin(t)-stən-tə-ˈnē-
instantaneously
ˌin(t)-stən-ˈtā-nē-əs-lē
adverb -nyəs-lē
instantaneousness noun
Synonyms
- immediate
- instant
- split-second
- straightaway
See all Synonyms & Antonyms 
Example Sentences
We got an almost instantaneous response from the company. the thunder following the flash of lightning was nearly instantaneous
Recent Examples on the Web Even using fentanyl through such a method wouldn't have the instantaneous effect like those described in social media claims, Nelson said. 
Brieanna J. Frank, USA TODAY, 9 Sep. 2022 In a 2019 Vogue interview, Teller reflected on their first encounter and their instantaneous connection. Nasha Smith, Peoplemag, 23 Aug. 2022 Michelangelo’s image of God’s finger touching Adam’s, endowing the creature with the instantaneous gift of human life, seemed fixed in the Western consciousness. James Carroll, The New Yorker, 19 Aug. 2022 The evacuation, unprecedented in scale, was carried out over the last two weeks of August 2021, after the Taliban swept into Kabul, the capital, forcing the U.S.-backed government’s instantaneous collapse. Tim Craig, Washington Post, 14 Aug. 2022 What can be even worse in our culture in which instantaneous responses have become the norm is knowing that someone has seen a message and isn't responding to you. Kara Alaimo, CNN, 10 Aug. 2022 The $4 million drop to $12 million for a six-bedroom, nine-bath mansion with a Mickey suite and a 900-bottle wine gallery made an instantaneous difference, said Renner of Nectar Real Estate, in a report from GrowthSpotter. Dustin Wyatt, Orlando Sentinel, 4 Aug. 2022 Along with open APIs and DevOps, cloud-native architecture provides near instantaneous scalability, deployment and redeployment to any cloud platform for optimized flexibility, upgrades and partner ecosystems. Ari Banerjee, Forbes, 3 Aug. 2022 It’s powered by a single electric motor that can generate up to 125 hp and 265 ft lbs of instantaneous torque. Bryan Hood, Robb Report, 7 July 2022 See More
Brieanna J. Frank, USA TODAY, 9 Sep. 2022 In a 2019 Vogue interview, Teller reflected on their first encounter and their instantaneous connection. Nasha Smith, Peoplemag, 23 Aug. 2022 Michelangelo’s image of God’s finger touching Adam’s, endowing the creature with the instantaneous gift of human life, seemed fixed in the Western consciousness. James Carroll, The New Yorker, 19 Aug. 2022 The evacuation, unprecedented in scale, was carried out over the last two weeks of August 2021, after the Taliban swept into Kabul, the capital, forcing the U.S.-backed government’s instantaneous collapse. Tim Craig, Washington Post, 14 Aug. 2022 What can be even worse in our culture in which instantaneous responses have become the norm is knowing that someone has seen a message and isn't responding to you. Kara Alaimo, CNN, 10 Aug. 2022 The $4 million drop to $12 million for a six-bedroom, nine-bath mansion with a Mickey suite and a 900-bottle wine gallery made an instantaneous difference, said Renner of Nectar Real Estate, in a report from GrowthSpotter. Dustin Wyatt, Orlando Sentinel, 4 Aug. 2022 Along with open APIs and DevOps, cloud-native architecture provides near instantaneous scalability, deployment and redeployment to any cloud platform for optimized flexibility, upgrades and partner ecosystems. Ari Banerjee, Forbes, 3 Aug. 2022 It’s powered by a single electric motor that can generate up to 125 hp and 265 ft lbs of instantaneous torque. Bryan Hood, Robb Report, 7 July 2022 See More Word History
Etymology
Medieval Latin instantaneus, from instant-, instans, noun
First Known Use
1651, in the meaning defined at sense 1
Kids Definition
instantaneous
adjective
in·stan·ta·neous ˌin-stən-ˈtā-nē-əs
: happening or done very quickly : happening in an instant
an instantaneous reply
instantaneously
adverb
as in immediately
without delay I had just slammed the car door shut when I instantaneously remembered that I had left the keys inside Synonyms & Similar Words
Relevance
- immediately
- instantly
- promptly
- now
- directly
- right
- quickly
- suddenly
- shortly
- soon
- away
- forthwith
- straightaway
- instanter
- incontinently
- at once
- bang
- straightway
- right off
- rapidly
- right now
- straight off
- presently
- swiftly
- right away
- pronto
- abruptly
- headlong
- momentarily
- off the bat
- freely
- readily
- plumb
- quick
- in no time
- speedily
- fast
- on the double
- on a dime
- on the spot
- unexpectedly
- hastily
- swift
- PDQ
- briskly
- impulsively
- apace
- anon
- presto
- posthaste
- fleetly
- impetuously
- recklessly
- rashly
- punctually
- full tilt
- opportunely
- seasonably
- snappily
- exactly
Antonyms & Near Antonyms
- slowly
- late
- tardily