a feeling of doubt, suspicion, or misgiving about the truth or adequacy of something; not being fully convinced.
記者会見で彼の説明に多くの疑念が残った。
Many doubts remained about his explanation at the press conference.
その報告書の信頼性に疑念を抱く研究者がいる。
Some researchers have doubts about the reliability of that report.
疑念を解くために、追加の証拠が必要だ。
Additional evidence is needed to dispel the doubts.