white line

American  

noun

1. a stripe of white paint, tiles, or the like, that marks the center or outer edge of a road.

2. a white layer in a horse's hoof.

3. any blank or white part, line, stripe, or margin.

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white line British  

noun

1. a line or strip of white in the centre of a road to separate traffic going in different directions

2. a white lamination in the hoof of a horse

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Etymology

Origin of white line

First recorded in 1590–1600

Example Sentences

Verstappen was given a five-second penalty for crossing the white line at the pit exit, which underlines an underwhelming Sunday.

From BBC • May 3, 2026

“After the click, the video display shut down with only a white line visible to crew members.”

From Seattle Times • Dec. 28, 2023

Whatever boardroom activities are taking place has nothing to do with a professional footballer once they cross the white line.

From BBC • Sep. 17, 2023

Beyond lie the turquoise and azure waters of the lagoon, a white line of surf at the reef, cumulus clouds on the horizon moving as stately as galleons.

From Slate • Aug. 5, 2023

She could only stare at the white line of chalk that marked the ring.

From "Throne of Glass" by Sarah J. Maas