ENGLISH
REFERENCE

upset

v. · adj. · n.
US //ˈəpˌsɛt// up·set
Irregular verb past upset past participle upset
  1. 1 to make someone sad (v.)
    B1 Intermediate

    to make someone feel unhappy, worried, or angry.

    to disturb the emotional state of a person, causing distress or agitation. Transitive — requires a person or group as the object.

    Example

    I am sorry if my comments about the project upset you.

    Example

    The news of the sudden layoffs upset the entire department, leading to a significant drop in morale and productivity.
  2. 2 to disrupt a plan (v.)
    B2 Upper Intermediate

    to change a plan or situation so that it no longer works well.

    to disturb or adversely alter the typical order, state, or functioning of something.

    Example

    The sudden rainstorm upset our plans for a picnic in the park.

    Example

    The unexpected shift in interest rates threatened to upset the delicate balance of the national economy.
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  1. 3 to knock over (v.)
    B2 Upper Intermediate

    to accidentally push something over so that it falls.

    to tip over or overturn an object, typically by accident.

    Example

    The cat jumped on the table and upset a glass of water.

    Example

    The gust of wind was strong enough to upset the small sailing boat, forcing the crew to swim to shore.
  2. 4 feeling sad or angry (adj.)
    B1 Intermediate

    feeling unhappy, worried, or angry because of something bad that happened.

    distressed or agitated in mind or feelings. Often used predicatively after a linking verb.

    Example

    She was very upset when she heard that she didn't get the job.

    Example

    The residents were visibly upset by the council's decision to demolish the historic community centre.
  3. 5 feeling sick (adj.)
    B1 Intermediate Medicine

    feeling like you might vomit or having a stomach ache.

    relating to a physical state of nausea or gastrointestinal distress.

    Example

    I have an upset stomach after eating that spicy seafood last night.

    Example

    The patient reported feeling generally upset and nauseated following the administration of the new medication.
  4. 6 an unexpected win (n.)
    B2 Upper Intermediate Sport

    a situation where a person or team wins when they were expected to lose.

    an unexpected victory by an underdog in a sporting or political contest.

    Example

    The local team's victory over the champions was the biggest upset of the season.

    Example

    Political analysts were stunned by the electoral upset, as the newcomer defeated the incumbent by a significant margin.
  5. 7 aircraft loss of control (n.)
    C2 Proficiency Technical Aviation

    a dangerous situation where a plane is not flying correctly and the pilot might lose control.

    an aircraft state characterized by unintended departures from the normal flight envelope, requiring immediate recovery actions.

    Example

    The pilot was trained to recover the plane from a sudden upset during a storm.

    Example

    The flight data recorder indicated that the aircraft entered an upset condition shortly after the autopilot disengaged in heavy turbulence.

  6. 8 mathematical set (n.)
    C2 Proficiency Technical Math

    a special group of numbers or items in math where if one item is included, all 'larger' items are too.

    a subset of a partially ordered set such that if an element is in the subset, all elements greater than it are also included.

    Example

    In this diagram, the shaded area represents an upset in the ordered group.

    Example

    The researcher demonstrated that the intersection of any two upsets in a partially ordered set is itself an upset.
    • downset
Origin

From Middle English upset (“the act of setting up; establishment”), from Middle English upsetten, corresponding to up- + set. Cognate with Middle Low German upset (“setup; arrangement”).

Idioms1 entry

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