noun
qualm
KWAHM/kwɑːm/
An uneasy feeling of doubt about whether something is right.
He feels a qualm about keeping the cash from the lost wallet.

Etymology
The modern sense developed from physical faintness into uneasiness and then moral scruple. A link to Old English cwealm, meaning death or torment, is plausible but lacks a documented direct path.
In context
In the presence of others she might now and again have a qualm or a doubt; but not with her.
More examples
- She has no qualms about returning a gift she dislikes.
- A sudden qualm stops me from reading his private messages.
- Despite his qualms, he agrees to keep the mistake a secret.
Forms
qualm · qualms
Similar words
- scruple
- More specifically a moral objection based on personal principles.
- misgiving
- Usually concerns possible problems rather than right and wrong.