When you feel upset & fell that someone did you dirty. Usually when you feel this way you haven't & don't plan on telling them that you think they were unfair to you in some way.

When you do something or make a decision based on pleasing somebody else. The important factor is that the direction you took (the action or decision) was taken only to satisfy the other person and not something you would have normally chosen to do. Regret surfaces and you secrectly hold it against that person. You may or may not take it out on them, but it does eat you up inside.

When you take the poison and expect someone else to die.

A feeling of bitterness for someone, something, an event, etc..

when you get a quiet thought or idea. also can mean an expression of something.