criticality
noun
crit·i·cal·i·ty
ˌkri-tə-ˈka-lə-tē 
: a critical quality, state, or nature
The true criticality of that basic political rationale is being demonstrated in the 1990s.—
Colin S. Gray
Colin S. GrayBut the inspector general of the Department of Homeland Security, in a report released Tuesday, found that the list was not child's play: all these "unusual or out-of-place" sites "whose criticality is not readily apparent" are inexplicably included in the official federal antiterrorism database.—Eric Lipton
Eric Lipton
specifically, physics
: the state in which a mass of fissionable material sustains or is able to sustain a nuclear chain reaction
Criticality can be achieved by increasing mass (adding more plutonium) or … by compressing a barely subcritical mass to increase its density. —Daniel J. Lenihan
Daniel J. Lenihan How big is a critical mass? That depends on the proportion of fissile material and on its shape and configuration. Surrounding the mass with a neutron-reflecting substance further reduces the size needed for criticality, by returning neutrons that would otherwise escape. —Richard Wolfson
Richard Wolfson Examples of criticality in a Sentence
Recent Examples on the Web
Aalo Atomics has accelerated its push toward a 2026 first criticality goal by shipping five nuclear reactor test modules to the Idaho National Laboratory (INL).
—Aman Tripathi, Interesting Engineering, 21 Dec. 2025
The race to meet the US Department of Energy Reactor Pilot Program's deadline of having a reactor achieving criticality by July 4 next year is on.
—Abhimanyu Ghoshal, New Atlas, 18 Dec. 2025
Despite their criticality, maintenance and monitoring remains vastly underfunded.
—Andrew Paul, Popular Science, 17 Dec. 2025
The criticality in being able to operate with agility, efficacy, and speed to stop breaches is having the data that controls and the actions in a single platform, not multiple platforms.
—Zev Fima, CNBC, 3 Dec. 2025
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Aman Tripathi, Interesting Engineering, 21 Dec. 2025
The race to meet the US Department of Energy Reactor Pilot Program's deadline of having a reactor achieving criticality by July 4 next year is on.
—Abhimanyu Ghoshal, New Atlas, 18 Dec. 2025
Despite their criticality, maintenance and monitoring remains vastly underfunded.
—Andrew Paul, Popular Science, 17 Dec. 2025
The criticality in being able to operate with agility, efficacy, and speed to stop breaches is having the data that controls and the actions in a single platform, not multiple platforms.
—Zev Fima, CNBC, 3 Dec. 2025
See All Example Sentences for criticality
Cite this Entry
“Criticality.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/criticality. Accessed 25 Dec. 2025.
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