transitive verb upset -·set′, upsetting -·set′·ting

1. Obsolete to set up; erect
2. 1. to tip over; overturn to upset a vase
   2. to overthrow or defeat unexpectedly
3. 1. to disturb the functioning, fulfillment, or completion of to upset a busy schedule
   2. to disturb mentally or emotionally upset by bad news
   3. to disturb physically; make sick to upset the stomach
4. Mech.
   1. to shorten and thicken (a red-hot iron) by beating on the end
   2. to shorten (a metal tire) in the process of resetting it

Etymology: ME upsetten: see up & set

intransitive verb

noun

1. an upsetting or being upset; specif.,
   1. a tipping over, knocking over, etc.
   2. an unexpected victory or defeat
   3. a disturbance or disorder, specif. of an emotional or physical nature
2. Mech.
   1. a swage used for upsetting
   2. an upset piece or part

adjective

1. Rare set up; erected
2. 1. tipped over; overturned
   2. disturbed or disordered