Upset (disambiguation)

Upset may refer to:

• Upset, in a competition where a likely winner loses to an underdog.
• Upset forging, a forging process where a workpiece's diameter is increased by compressing its length.
• Depression (mood), upset emotionally.
• Upset (wastewater treatment), temporarily decreased effluent quality
• Upset (horse), the only thoroughbred horse to defeat the racehorse Man o' War.
• Upset (chemical release), an unplanned release of toxic emissions by chemical processing plants
• Upper set, (in mathematics), also called an upward closed set or just an upset, is a subset Y of a given partially ordered set (X,≤) such that, for all elements x and y, if x is less than or equal to y and x is an element of Y, then y is also in Y.
• Aircraft upset (in aviation), a dangerous condition in aircraft operations which may result in the loss of control of the aircraft