Apprehensive

1. adjective

   mentally upset over possible misfortune or danger etc

   “apprehensive about her job”

   Similar: worried

2. adjective

   quick to understand; - Nathaniel Hawthorne

   “a kind and apprehensive friend”

   Similar: discerning

3. adjective

   in fear or dread of possible evil or harm

   “apprehensive for one's life”