Also found in: Thesaurus, Acronyms, Encyclopedia, Wikipedia.
1. A line that bisects something into equal parts.
2. A painted line running along the center of a road or highway that divides it into two sections for traffic moving in opposite directions, or, in the case of a divided highway, for lines of traffic moving in the same direction at different speeds.
or cen′ter line`,
any line that bisects a plane figure: the centerline of a building plan.