- Historical a strong wooden fort with a projecting second story and openings in the walls for the defenders to shoot from
- any building of squared timber or logs
- Mil. a small defensive structure of concrete
- a dome-shaped, heavily reinforced structure, with periscopes and detecting instruments, to protect observers of missile launchings, nuclear explosions, etc.
- A military fortification constructed of sturdy material, such as concrete, and designed with ports for defensive firing or observation.
- A heavily reinforced building used for launch operations of missiles and space launch vehicles.
- A fort made of squared timbers with a projecting upper story.
- The fifth, and last period - which, after all other expedients had failed, finally brought the residue of uncaptured and unsurrendered burghers to submission - was the final development of the blockhouse system, wedded to the institution of systematic. " driving " of given areas, which operations were in force until the 31st of May 1902, when peace was ratified at Pretoria.
- In 1497 a blockhouse was built at the harbour mouth as a protection against the English.
- The next stage was that which saw the slow building up of the blockhouse system and the institution of small punitive columns, and may be considered to have extended until the close of 1901.
- The establishment of a line of defensive posts between Bloemfontein and Ladybrand, though De Wet had three times traversed it, had given Blockhouse Policy.
- By the end of the year the blockhouse system was complete, but this phase of the war was destined to close badly as De Wet on Christmas Eve captured a large force of Yeomanry at Tweefontein, west of Harrismith.