Definition of outbreak
1a
: a sudden or violent increase in activity or currency
the outbreak of war
b
: a sudden rise in the incidence of a disease
an outbreak of measles
c
: a sudden increase in numbers of a harmful organism and especially an insect within a particular area
an outbreak of locusts
2
: insurrection, revolt
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Merriam-Webster unabridged
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Time Traveler for outbreak
The first known use of outbreak was in 1562
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