Meanings

distance in a straight line

lines in operation

incident ray

cherry blossom front

ridgeline

catgut

train derailment due to a concurrence of causes

toy fireworks

finish line

(one's) gaze

high-voltage wire

high-water mark

harbor railroad

geodesic (line)

infrared photography

four-track rail line (two in each direction)

double track

anode ray

lifeline

downward curve