外がい線せん

noun

outside telephone line; external line

Refers to a telephone line that connects to outside numbers, as opposed to an internal extension (内線).

• 外がい線せんに出でるには、最さい初しょにゼロを押おしてください。

  To get an outside line, please press zero first.

• 外がい線せんが混こみ合あっていて、なかなかつながらない。

  The outside lines are busy and I can't get through.

noun

outer circle; outer line

Used in geometry or technical contexts for an external circle or line, such as in diagrams or sports fields.

• この図ず形けいの外がい線せんの長ながさを計けい算さんしてください。

  Calculate the length of the outer line of this figure.