upset

Angry, distressed, or unhappy

He was upset when she refused his friendship.

My children often get upset with their classmates.

Feeling unwell, nauseated, or ready to vomit.

His stomach was upset, so he didn't want to move.

Bryan came home from school with an upset tummy.

Disturbance or disruption.

My late arrival caused the professor considerable upset.

An unexpected victory of a competitor or candidate that was not favored to win.

But it is probably the biggest upset for the away side since Ronnie Radford smashed a famous goal as Hereford defeated Newcastle 2-1 in 1972.

Sanders’s win in Michigan was one of the greatest upsets in modern political history.

An overturn.

"collision and upset": impact with another object or an overturn for whatever reason.

An upset stomach.

“Bob, let's cancel the baby sitter. With this upset stomach, I can't go out tonight.” “Sure you can, Liz! Try Pepto-Bismol. Hospital tests prove it relieves upsets. And it's great for indigestion or nausea, too!”

An upper set; a subset (X,≤) of a partially ordered set with the property that, if x is in U and x≤y, then y is in U.

To make (a person) angry, distressed, or unhappy.

I’m sure the bad news will upset him, but he needs to know.

To disturb, disrupt or adversely alter (something).

Introducing a foreign species can upset the ecological balance.

The fatty meat upset his stomach.

To tip or overturn (something).

1924, W. D. Ross translator, Aristitle, Metaphysics, Book 1, Part 9, The Classical Library, Nashotah, Wisconsin, 2001. But this argument, which first Anaxagoras and later Eudoxus and certain others used, is very easily upset; for it is not difficult to collect many insuperable objections to such a view.

To defeat unexpectedly.

Truman upset Dewey in the 1948 US presidential election.

To be upset or knocked over.

The carriage upset when the horse bolted.

[T]he locomotive exploded and upset, and was completely wrecked.