variants
or chiefly British aeon
1
: an immeasurably or indefinitely long period of time : age
I haven't seen him in eons.
2
a
: a very large division of geologic time usually longer than an era
the Archean eon
b
: a unit of geologic time equal to one billion years
Examples of eon in a Sentence
Recent Examples on the Web
Remember Mass Effect, the nearly 20 year old series everyone likes that has been doing this kind of thing for eons?
—
Paul Tassi, Forbes, 21 Mar. 2025
Later this year, the DES collaboration plans to publish observations of how galaxies and matter have clustered over the eons, a process that reflects the tug-of-war between gravity’s pull and dark energy’s push.
—Charlie Wood, Quanta Magazine, 19 Mar. 2025
Focusing on the late Archean eon (3 billion years to 2.5 billion years ago), Professor Eiichi Tajika and his team simulated crucial aspects of Earth’s biological, chemical, and geological history.
—Stephanie Edwards, Discover Magazine, 10 Mar. 2025
Yet questions about biological paternity have roiled families and fueled cultural anxieties for eons.
—Byandrew Curry, science.org, 6 Mar. 2025
See All Example Sentences for eon
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Paul Tassi, Forbes, 21 Mar. 2025
Later this year, the DES collaboration plans to publish observations of how galaxies and matter have clustered over the eons, a process that reflects the tug-of-war between gravity’s pull and dark energy’s push.
—Charlie Wood, Quanta Magazine, 19 Mar. 2025
Focusing on the late Archean eon (3 billion years to 2.5 billion years ago), Professor Eiichi Tajika and his team simulated crucial aspects of Earth’s biological, chemical, and geological history.
—Stephanie Edwards, Discover Magazine, 10 Mar. 2025
Yet questions about biological paternity have roiled families and fueled cultural anxieties for eons.
—Byandrew Curry, science.org, 6 Mar. 2025
See All Example Sentences for eon
Cite this Entry
“Eon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/eon. Accessed 2 Apr. 2025.
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