or cen·ter line

  1. any line that bisects a plane figure: the centerline of a building plan.
  2. a line along the center of a road or highway dividing it into separate sections for traffic moving in opposite directions.
  3. Radio. the perpendicular bisector of the line connecting two radio transmitters.

Origin of centerline

First recorded in 1800–10; center + line1 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for centerline

Historical Examples of centerline