A large concrete block with a groove in the bottom face and a tongue on the top face to eliminate slippage when they are stacked. There is also a steel loop on the top face to facilitate lifting. The blocks are stacked in an offset manner to create a wall for retaining earth by means of their great mass. A wall built with them can be readily dismantled and the blocks reused (in ecological fashion).

a metal block for supporting a rotating shaft; a bearing

(idiomatic) A hindrance, obstacle or impediment; an opportunity for error.

The (usually temporary) inability to begin or continue work on a piece of writing, especially creative writing.

(vulgar, slang) Alternative spelling of cockblock

(vulgar, slang) Alternative spelling of cockblock

(computing) An image that contains the sectors read from an original floppy disk or optical disc.

(aviation) The time from the moment the aircraft door closes at departure of a revenue flight until the moment the aircraft door opens at the arrival gate following its landing. Block hours are the industry-standard measure of aircraft utilization.

plural of block party

A festive event held in the street of a city block / (basketball, slang) A game during which a single player blocks the shots of many other players