"A negative thought is any thought of failure, disappointment, or trouble; any thought of criticism, or spite, or jealousy, or condemnation of others, or self-condemnation; any thought of sickness or accident; or, in short, any kind of limitation. In practice you will never have any trouble in knowing whether a given thought is positive or negative. Even if your brain tries to deceive you, your heart will whisper the truth." (Emmet Fox)
Any negative thought can form the basis for an entry in a resentment inventory.
Sometimes people say they have few resentments.
If resentment is defined as the generation of a negative reaction in response to something, then the above assertion is untrue.
There are hundreds a day.
The etymology of resentment is not about feeling again but feeling strongly in response to something.
The re is the re of rebound rather than reupholster.
To rebound is to bounce off. To resent is to feel off.