Distrust was an emotion that described a feeling of doubt or lack of confidence in someone or something.
In 2368, Spock said to Jean-Luc Picard, "I sense you have a closed mind, Captain. Closed minds have kept these two worlds apart for centuries. In the Federation, we have learned from experience to view the Romulans with distrust. We can either choose to live with that enmity or seek an opportunity to change it. I choose the latter." (TNG: "Unification II")