any elementary particle with a strangeness quantum number other than zero.
Origin of strange particle
First recorded in 1955–60; originally so called because of the anomalously long decay time of such particles
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Science definitions for strange particle
Any of various unstable elementary particles, having a short half-life and a nonzero strangeness quantum number. Sigma and xi baryons, for example, are strange particles.
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