Noun

1. A cue given to a performer (usually the beginning of the next line to be spoken)
2. (computer science) a symbol that appears on the computer screen to indicate that the computer is ready to receive a command

Verb

1. Give an incentive for action
2. Serve as the inciting cause of
3. Assist (somebody acting or reciting) by suggesting the next words of something forgotten or imperfectly learned