Noun

1. Someone employed to conduct others
2. Someone who shows the way by leading or advising
3. Something that offers basic information or instruction
4. A model or standard for making comparisons
5. Someone who can find paths through unexplored territory
6. A structure or marking that serves to direct the motion or positioning of something

Verb

1. Direct the course; determine the direction of travelling
2. Take somebody somewhere
3. Be a guiding or motivating force or drive
4. Use as a guide
5. Pass over, across, or through