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
Deployable Energy conducted the Unity criticality test under the Nuclear Energy Launch Pad initiative at INL.
—
Georgina Jedikovska,
Interesting Engineering,
2 July 2026
David Haber, a general partner at Andreesen Horowitz, believes the firm was smart to start with dispatch, given the criticality of this activity.
—
David Prosser,
Forbes.com,
25 June 2026
Ahead of Wright’s visit, two reactors achieved criticality.
—
Idaho Statesman,
25 June 2026
The executive order directed the Department of Energy to have three different reactor designs reach criticality in a bit over a year.
—
ArsTechnica,
5 June 2026
See All Example Sentences for criticality
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Georgina Jedikovska,
Interesting Engineering,
2 July 2026
David Haber, a general partner at Andreesen Horowitz, believes the firm was smart to start with dispatch, given the criticality of this activity.
—
David Prosser,
Forbes.com,
25 June 2026
Ahead of Wright’s visit, two reactors achieved criticality.
—
Idaho Statesman,
25 June 2026
The executive order directed the Department of Energy to have three different reactor designs reach criticality in a bit over a year.
—
ArsTechnica,
5 June 2026
See All Example Sentences for criticality
Cite this Entry
“Criticality.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/criticality. Accessed 5 Jul. 2026.
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