What is the meaning of suspicion (al-ẓann) mentioned in the Hadith: "Beware of suspicion, for suspicion is the most untruthful of speech," and is what is intended the sudden suspicion or the inherent suspicion?

The blameworthy suspicion is the heart's belief, accusing a Muslim of wrongdoing without justification, and then believing it and persisting in it, not merely fleeting thoughts. It is an accusation that has no basis, especially if the suspected person is known for modesty and righteousness. However, regarding someone who is known for committing sins, it is not forbidden to have ill suspicions about them. Not all suspicion is a sin; some of it is obligatory, recommended, or permissible.