Combined from Small [小] + Short thread [幺] + Water [水] + White [白] + Thread / Silk [糸] to compose 線: represents "line".
along railway line
main line, trunk line
three-stringed Japanese guitar, shamisen
dotted line, perforated line
electric line
wireless, radio
underline, underscore
curve
beam, light ray
bullet train (very high speed), shinkansen
horizon
line, track, roadbed
derailment, digression
straight line
phone extension, indoor wiring, inner line
horizon
line