—n. 1. the movement of vehicles, ships, persons, etc., in an area, along a street, through an air lane, over a water route, etc.: the heavy traffic on Main Street. 2. the vehicles, persons, etc., moving in an area, along a street, etc.
3. the transportation of goods for the purpose of trade, by sea, land, or air: ships of traffic. 4. trade; buying and selling; commercial dealings.
5. trade between different countries or places; commerce.
6. the business done by a railroad or other carrier in the transportation of freight or passengers.
7. the aggregate of freight, passengers, telephone or telegraph messages, etc., handled, esp. in a given period.
8. communication, dealings, or contact between persons or groups: traffic between the Democrats and the Republicans. 9. mutual exchange or communication: traffic in ideas. 10. trade in some specific commodity or service, often of an illegal nature: the vast traffic in narcotics.
—v.i. 1. to carry on traffic, trade, or commercial dealings.
2. to trade or deal in a specific commodity or service, often of an illegal nature (usually fol. by in): to traffic in opium.