A fortress is a large building or complex of buildings used as a military stronghold. In a military sense, a fortress is often called a “fort."

From its original sense of stronghold, the word fortress has stretched to include strongholds in a more figurative sense. Martin Luther used fortress to describe unfailing spiritual support when he wrote, “A mighty fortress is our God.” When someone has a hard time trusting others, you might say they have retreated to a "fortress of their own making."

Definitions of fortress
  1. noun
    a fortified defensive structure
    synonyms: fort
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    a fortified Moorish palace built near Granada by Muslim kings in the Middle Ages
    a fortress built in Paris in the 14th century and used as a prison in the 17th and 18th centuries; it was destroyed July 14, 1789 at the start of the French Revolution
    Tower of London
    a fortress in London on the Thames; used as a palace and a state prison and now as a museum containing the crown jewels
    Machu Picchu
    Inca fortress city in the Andes in Peru discovered in 1911; it may have been built in the 15th century
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    any of various Spanish fortresses or palaces built by the Moors
    martello tower
    a circular masonry fort for coastal defence
    a fortress established in the southwestern United States by the Spanish in order to protect their missions and other holdings
    a small fort or earthwork defending a ford, pass, or castle gate
    type of:
    defence, defense, defensive structure
    a structure used to defend against attack
Word Family

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