Mistrust

wiktionary

ref

mis- +‎  trust

etymonline

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mistrust (n.)

"lack of confidence, suspicion," late 14c., from mis- (1) "bad, wrong" + trust (n.). Related: Mistrustful; mistrustfulness.

mistrust (v.)

"doubt, regard with jealousy or suspicion," late 14c., mistrusten, from mis- (1) "badly, wrongly" + trust (v.). Related: Mistrusted; mistrusting.