mistrust

Short definition from Wiktionary

Noun

1. 1
   Lack of trust or confidence; distrust, untrust.

Verb

1. 1
   To have no confidence in (something or someone).
2. 2
   To be wary, suspicious or doubtful of (something or someone).
3. 3
   To suspect, to imagine or suppose (something) to be the case.
4. 4
   To be suspicious.