undefended
adjective
un·de·fend·ed
ˌən-di-ˈfen-dəd 
: not guarded or protected : not defended
left the goal undefended
an undefended frontier/border
Examples of undefended in a Sentence
the cowardly soldiers fled, leaving the palace undefended
Recent Examples on the Web
The buses usually took the Peace Bridge to cross the world’s longest undefended border, slowing to 30 mph over the Niagara River before pulling into the U.S. Customs and Border Protection processing center.
—
Tim Graham, New York Times, 9 July 2025
Yet after centuries of peace, with the two countries now sharing the longest undefended border in the world, the timing normally feels less like dueling celebrations than a week-long joint birthday party.
—Zack Beauchamp, Vox, 2 July 2025
Our two nations enjoy the world’s longest undefended border, largest trading partnership, and nearly a century of military cooperation, from the beaches of D-Day to the fight against al-Qaeda in Afghanistan.
—Ian Cooper, Sun Sentinel, 5 May 2025
Ukraine says that would amount to surrender and leave it undefended if Moscow attacks again.
—USA Today, 22 Apr. 2025
See All Example Sentences for undefended
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Tim Graham, New York Times, 9 July 2025
Yet after centuries of peace, with the two countries now sharing the longest undefended border in the world, the timing normally feels less like dueling celebrations than a week-long joint birthday party.
—Zack Beauchamp, Vox, 2 July 2025
Our two nations enjoy the world’s longest undefended border, largest trading partnership, and nearly a century of military cooperation, from the beaches of D-Day to the fight against al-Qaeda in Afghanistan.
—Ian Cooper, Sun Sentinel, 5 May 2025
Ukraine says that would amount to surrender and leave it undefended if Moscow attacks again.
—USA Today, 22 Apr. 2025
See All Example Sentences for undefended
Cite this Entry
“Undefended.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/undefended. Accessed 18 Jul. 2025.
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