crit·​i·​cal·​i·​ty | \ ˌkri-tə-ˈka-lə-tē How to pronounce criticality (audio) \

Definition of criticality

: a critical quality, state, or nature The true criticality of that basic political rationale is being demonstrated in the 1990s.— Colin S. Gray But 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 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 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

First Known Use of criticality

1824, in the meaning defined above

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The first known use of criticality was in 1824

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Dictionary Entries Near criticality

critical idealism


critical mass

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Cite this Entry

“Criticality.” Dictionary, Merriam-Webster, Accessed 16 May. 2022.

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