The meaning of INSTANTANEOUS is done, occurring, or acting without any perceptible duration of time. How to use instantaneous in a sentence.

It can be almost instantaneous, preparing us to respond to threats faster than our conscious minds can even assess a situation.

INSTANTANEOUS definition: occurring, done, or completed in an instant. See examples of instantaneous used in a sentence.

Definition of instantaneous adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

1. Occurring or completed without perceptible delay: Relief was instantaneous. 2. Done or made as quickly or directly as possible: an instantaneous reply to my letter. 3. Present or occurring …

Something that is instantaneous happens immediately and very quickly. Death was instantaneous because both bullets hit the heart.

Dec 14, 2025 · Adjective instantaneous (not comparable) Occurring, arising, or functioning without any delay; happening within an imperceptibly brief period of time. [from 17th c.] Synonyms: …