traffic
Pronunciation: /ˈtrafɪk/
noun
- 1vehicles moving on a public highway: a stream of heavy traffic
- the movement of ships, trains, aircraft, or pedestrians: Europe’s air traffic
- the transportation of goods or passengers: the increased use of railways for goods traffic
verb ( traffics, trafficking, trafficked)

Origin:
early 16th century (denoting commercial transportation of merchandise or passengers): from French traffique, Spanish tráfico, or Italian traffico, of unknown origin. Sense 1 dates from the early 19th century

Spelling rule
If a verb ends in -ic (as in picnic), add a k after the c when adding -ed, -ing, and -er: