at any time

horizon on water / a horizontal or level line (perpendicular to the force of gravity)

horizon on land

(geometry, engineering) extended line (usually as an auxiliary line) / extension of a traffic route (e.g. highway or railway line) / (figuratively) extension or result developed from an existing thing

(technology) Synonym of アンテナ (antena, “antenna”); an aerial (device for receiving or transmitting)

borders (outer lines) of a box

copper wire

reticle; crosshair

(acoustics, physics) a sound ray, an acoustic ray

rough lines of a rough sketch