What does contraflow mean?

Question

What does contraflow mean?

Answer 1

This is all I could find:

Contraflow lane reversal is used to refer to plans that alter the normal flow of traffic, typically on a controlled-access highway such as a freeway or motorway, to either aid in an emergency evacuation (the most common usage of the term in the United States) or, as part of routine maintenance activities, to facilitate widening or reconstruction of one of the highway's carriageways