うたがutagau
1.

To think that something may not be true or that a certain situation does not exist, indicating a lack of belief or confidence in its validity or authenticity.

2.

To hold a suspicion that a specific individual might be involved in wrongdoing or ill intent, raising concerns about their character or actions.

3.

To approach an ambiguous situation with a negative or pessimistic mindset, contemplating the possibility that the outcome may not be favorable or sincere.

Example:

僕の言葉をまだ疑っているんですか。