mistrustfully

This adverb describes an attitude of skepticism or caution, typically manifesting as a guarded emotional state. It suggests a proactive suspicion where the subject is actively looking for signs of deception or betrayal, rather than a passive lack of faith.

In terms of register, it is a standard descriptive term used in both narrative prose and formal reports to characterize a person's demeanor. It is more specific than "suspiciously," as it emphasizes the absence of trust specifically, whereas "suspiciously" can refer to any perceived irregularity or illegal activity.