What it means

1. adjective mildly physically distressed
   “an upset stomach”
2. adjective having been turned so that the bottom is no longer the bottom
   “an overturned car”
3. adjective thrown into a state of disarray or confusion
   “troops fleeing in broken ranks”
4. adjective afflicted with or marked by anxious uneasiness or trouble or grief
   “too upset to say anything”
5. noun the act of upsetting something
   “he was badly bruised by the upset of his sled at a high speed”
6. noun the act of disturbing the mind or body
   “his carelessness could have caused an ecological upset”
7. noun a tool used to thicken or spread metal (the end of a bar or a rivet etc.) by forging or hammering or swaging
8. noun an improbable and unexpected victory
   “the biggest upset since David beat Goliath”
9. noun a physical condition in which there is a disturbance of normal functioning
   “the doctor prescribed some medicine for the disorder”
10. noun an unhappy and worried mental state
    “there was too much anger and disturbance”
11. verb disturb the balance or stability of
    “The hostile talks upset the peaceful relations between the two countries”
12. verb defeat suddenly and unexpectedly
    “The foreign team upset the local team”