block signal

American  

noun

1. a fixed railroad signal governing the movements of trains entering and using a given section of track.

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Other Word Forms

• block signaling
  noun

Etymology

Origin of block signal

First recorded in 1880–85

Example Sentences

In most nerve agent fatalities, death occurs after the agent binds to enough AChE to block signal transmission from the brain's respiratory center to the diaphragm, paralyzing the muscle that's vital for breathing.

From Science Magazine • Jan. 4, 2018

Apparently disregarding a warning block signal, apparently blind to the glare of No. lys's approaching headlight, Motorman Jacob Kiefer took No. 192 down the section of double track and roared on into the gantlet.

From Time Magazine Archive

Disaster whines through the cab window, for the prostrate engineer has not seen the block signal, his throttle yawns unheeded.

From Time Magazine Archive

But when the leading 6:09 was still a mile from the station, an overhead block signal ordered a temporary halt and its motorman obediently applied his brakes.

From Time Magazine Archive

This had been successfully accomplished for moderately heavy electric railway traffic in the Boston elevated installation, which was the first electric railway to adopt a complete automatic block signal system with track circuit control.

From The New York Subway Its Construction and Equipment by Anonymous