fort
 
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SMART Vocabulary: related words and phrases

Fortifications
acropolis
barricade
bastion
battlements
castle
citadel
drawbridge
earthwork
enceinte
entanglement
fort
Martello tower
moat
moated
motte
motte-and-bailey castle
pillbox
storm cellar
stronghold
turret

Examples from literature

Around the fortress are seven circular mounds, which at first suggest the idea of being the work of mound-builders. 
Have we destroyed the fleets of our enemies, fired their towns, and laid their fortresses in ruins? 
The fortress is separated from the town by a small bay, across which a wooden bridge has been built. 
The sultan immediately dispatched an army of two hundred thousand men to the relief of his beleaguered fortress. 
Yet at this moment the great fortress and arsenal lay at their mercy. 

fortress | American Dictionary

fortress
noun[ C ]
us/ˈfɔr·trəs/
a large, strong building or group of buildings that can be defended from attack

Examples of fortress

fortress
People are feeling insecure; they want their home to be a fortress.
It can be used for a fortress of any architectural type.
Unfortunately this is the only burial of its sort to be observed in a legionary fortress.
At which time you will be billed for all costs incurred to the fortress during your stay in the cage.
It is, therefore, an implicit fortress, and gives no hint whatsoever of the generous gardens within.
This suggests that women within this fortress are most probably officers' families and tradespersons, although the ordinary soldiers' barracks have not been extensively excavated.
This was passed with some enthusiasm after a conference discussion which at times seemed to be likening the new estates to socialist fortresses.
I doubt whether ' fortress conservationists ' will be convinced by this volume, since narratives generally are not judged by their actual achievements.
From the very beginning the body was considered a "fortress" constantly under attack by "the evil," by "bugs," and - inherited from premedical ages - by demons.
The assumption was that the guerrillas would be trapped in their main fortress as the strike forces converged inward.
At the far end, where the windows must have been, there were bass enclosures like fortresses on which midranges, trebles and supertrebles perched like turrets.
He lamented that even this fortress was no longer safe from the epidemic.
But at the same time those who settled employed architecture to build houses like fortresses.
The unions are necessary as a defensive fortress for all workingmen.
To this end, we are directed to the economic, administrative, and symbolic roles of the fortress within the rural context.
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