A teacher might use a verbal prod when students aren't participating in class. A prod is an encouragement, like the threat of a quiz. Just hope the teacher doesn't use the kind of prod a rancher uses to keep cattle moving!
Prod can also be a verb that refers to a soft poke or a nudge, like when you prod someone in the ribs with your finger. It can also describe verbal encouragement that's used when you want something or want to know something. For example, you might prod your sister into helping you do your math homework.