Upset is defined as to disturb physically, mentally or emotionally.(verb)
Upset means disturbed or sad.(adjective)
An example of upset is a person who has just learned that she did not get into her top choice school.
The definition of an upset is an unexpected victory.(noun)
An example of upset is an underdog team winning over the champions.
See upset in Webster's New World College Dictionary
Origin: ME upsetten: see up & set
See upset in American Heritage Dictionary 4
verb up·set, up·set·ting, up·sets verb, transitive
Origin: Middle English upsetten, to set up
Origin: : up-, up-
Origin: + setten, to set; see set 1.
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