How to say "disbelief" in Japanese

• 不信ふしんCommon
  nounDisbelief in the sense of distrust: refusing to believe in or trust a person, group, or institution. Its core senses are distrust and mistrust, fitting lost faith in a government rather than shock at news.
  花子はなこは不信ふしんに思おもって本当ほんとうかどうか問といただした。↗

  Hanako questioned his sincerity.
• 懐疑かいぎCommon
  noun, suru verb, transitive verb, intransitive verbDisbelief as skepticism: a considered, intellectual doubt about whether claims, statements, or theories are true. It names a questioning attitude of the mind, not the stunned feeling of being unable to believe what one sees.

Use 不信 for disbelief as distrust or lost faith in a person or institution, and 懐疑 for disbelief as skeptical doubt about claims or statements; neither is the word for stunned astonishment at surprising news.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 不信ふしんdistrust
• 懐疑かいぎdoubt