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Synonyms

simultaneity

American  
[sahy-muhl-tuh-nee-i-tee, sim-uhl-, -ney-] / ˌsaɪ məl təˈni ɪ ti, ˌsɪm əl-, -ˈneɪ- /
Sometimes simultaneousness

noun

  1. the state or quality of existing, occurring, or operating at the same time.

    The simultaneity of the two events was established by checking timestamps on recordings.


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In the meantime, we need realistic strategies for coping with simultaneity.

From The Wall Street Journal • Mar. 6, 2026

So many things of both celestial and terrestrial nature happened at once in Washington on Tuesday that their simultaneity seemed to require attention.

From Washington Post • Mar. 7, 2023

We tag along for a visit to a genteel gallery opening in St. Gallen, Switzerland, but what sticks in the mind is Motherwell’s self-aware observations about the simultaneity of art movements.

From New York Times • Jun. 16, 2022

About midway, Nolan spectacularly ramps up this backward-forward simultaneity: a battle sequences involves a “temporal pincer movement,” with two army detachments working together, but in different directions in time.

From Los Angeles Times • Aug. 21, 2020

Perhaps tomorrow someone will invent a theory consistent with everything else we know that circumvents paradoxes on such matters as simultaneity, avoids privileged reference frames and still permits travel faster than light.

From "Cosmos" by Carl Sagan