(railways) One of the danger signals or safety signals which guide the movement of trains in a block system, often coupled with a switch so that opening or closing the switch also operates the signal.

Woodblock printing, a style of printing (common in China and Japan) from engraved boards by means of a sheet of paper laid on the linked surface and rubbed with a brush.

(railways) A block in which two or more trains are permitted to travel, with certain restrictions.

Alternative form of chockablock

Alternative form of chockablock

Alternative form of cellblock

apartment building

A tall residential or office building.

plural of block length

(computing) The length (in bytes, characters, etc.) of a block of data.