noun
A feeling of distrust or suspicion toward someone or something. Often used with verbs like 抱く (to harbor) or 持つ (to have).
彼の説明に不信感を抱いた。
I felt distrust toward his explanation.
長年の不信感が両者の関係を悪化させた。
Years of distrust worsened the relationship between the two.
疑い is a broader term for doubt or suspicion, not necessarily implying a deep-seated feeling of distrust like 不信感.
Compound of 不信 (distrust, lack of faith) and 感 (feeling, sensation).