Mistrust means to doubt someone's honesty, reliability, or intentions. When you mistrust someone, you question whether they're telling the truth or whether they'll do what they promised. It's that uneasy feeling that makes you think twice before believing what someone says.

You might mistrust a classmate who's broken promises before, or mistrust a website that looks suspicious. Maybe you've learned to mistrust the weather forecast after it predicted sunshine right before a rainstorm. Mistrust often grows from experience: when someone lets you down repeatedly, you naturally start to mistrust them.

Mistrust is different from simple disagreement. You can disagree with your friend about which movie is better while still trusting them completely. But if that friend keeps sharing your secrets after promising not to, mistrust creeps in.

The word can be a verb (“I mistrust his motives”) or a noun (“She viewed the offer with mistrust”). Once mistrust takes root between people, rebuilding trust requires consistent honesty over time. A single apology rarely fixes it. Trust is built slowly through reliable actions, but mistrust can appear quickly when someone proves untrustworthy.