Related Clues:

• One in line at a station
• It's called on the street
• Airport lurker
• Medallioned vehicle
• Rental car of a sort
• Flagged vehicle
• Big rig compartment
• Tourist transport
• Hailed ride
• Half- -- (coffee order)
• Part of an 18-wheeler
• Enclosed part of a locomotive
• City hail
• Sharable ride
• 18-Across, e.g.