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Synonyms

citadel

American  
[sit-uh-dl, -uh-del] / ˈsɪt ə dl, -əˌdɛl /

noun

  1. a fortress that commands a city and is used in the control of the inhabitants and in defense during attack or siege.

  2. any strongly fortified place; stronghold.

  3. (formerly) a heavily armored structure on a warship, for protecting the engines, magazines, etc.


citadel British  
/ -ˌdɛl, ˈsɪtədəl /

noun

  1. a stronghold within or close to a city

  2. any strongly fortified building or place of safety; refuge

  3. a specially strengthened part of the hull of a warship

  4. (often capital) the headquarters of the Salvation Army

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of citadel

1580–90; < Middle French citadelle < Old Italian cittadella, equivalent to cittad ( e ) city + -ella -elle

Explanation

A citadel is a fortified structure designed to provide protection during a battle. So, back in the days when pillaging was commonplace, it was a good idea to know where your nearest citadel was. Among the most historically famous citadels are the Acropolis in Athens and the Tower of London. Even though we're building fewer physical fortresses these days, citadel remains a useful word, particularly when you need to create a metaphor suggesting strength and safety. As poet John Keats wrote, "[I]t appears to me that almost any man may like the spider spin from his own inwards his own airy citadel."

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Vocabulary lists containing citadel

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Closer to the border, the citadel in the village of Shamaa was also partly destroyed by the Israeli military.

From Barron's • Mar. 24, 2026

The recently opened IG Arena stands in the outer citadel of Nagoya Castle in Nagoya, Japan, which was built in the early 1600s, when samurai battles raged in the region.

From Los Angeles Times • Jul. 23, 2025

Peru is home to many of the Americas' most significant archaeological discoveries, including the Inca citadel of Machu Picchu in the Andes and the mysterious Nazca Lines etched into the desert along the central coast.

From BBC • Jul. 6, 2025

During a lull in heavy rain late Friday, a torchbearer lit a cauldron in front of the 2,500-year-old Parthenon temple, on the citadel that dominates the Athens skyline and is Greece’s top tourist draw.

From Seattle Times • Apr. 19, 2024

She said coolly, “When it comes to the defense of the citadel and our five lives...yes, you are.”

From "Strange the Dreamer" by Laini Taylor