経由

1. Origins, structure, and basic meaning

• Structure: 経由 is read as けいゆ and functions as a noun or with する for passing through a place, person, or route on the way to a destination.
• Basic usage: Mark the intermediate point with を in 駅を経由して or 担当者を経由して.

2. Common pitfalls and similar expressions

• Intermediate point versus destination
  • The item followed by 経由 is a waypoint, not the final destination, which is expressed separately with a particle such as へ.
• Physical and procedural routes
  • It applies both to a train passing through a station and to a document moving through a responsible staff member.