UNDEFENDED Synonyms: 49 Similar and Opposite Words

undefended

adjective

ˌən-di-ˈfen-dəd

Definition of undefended

as in vulnerable

lacking protection from danger or resistance against attack the cowardly soldiers fled, leaving the palace undefended

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Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of undefended The lack of range of Coastal Command aircraft left an undefended area known as the Mid-Atlantic Gap, rendering merchant shipping and their escorts without air cover and vulnerable to attack. — Mark Wood, TheWeek, 7 Jan. 2026 Trouba opened the scoring in the first period with an undefended slap shot after an egregious Blackhawks turnover. — CBS News, 7 Dec. 2025 Mark Collins, who was born and raised in Newfoundland, Canada, said Canadians have long treasured their friendship with the United States and the fact that the US-Canada border is the longest undefended border on the planet. — Matt Egan, CNN Money, 13 Oct. 2025 Like the global undersea cable network, the United States’ deep-water drilling infrastructure is rapidly expanding while remaining almost entirely undefended. — Robert Martinage, Foreign Affairs, 1 Jan. 2015 See All Example Sentences for undefended

Recent Examples of Synonyms for undefended

Adjective

The European Union has banned AI that encourages dangerous behavior in vulnerable groups like children, and mandated transparency requirements for other chatbots.

— Stephanie Yang, CNN Money, 23 July 2026
Chiggers are soft bodied and are vulnerable to sharp microscopic material in diatomaceous earth.

— Barbara Gillette, The Spruce, 22 July 2026

Definition of vulnerable

Adjective

However, declining vaccination rates fueled by vaccine hesitancy have created pockets of susceptible individuals where the virus can spread quickly.

— Omer Awan, Forbes.com, 24 July 2026
The emotional discomfort is a result of feeling self-conscious about the appearance, and the physical is typically the result of excess tissue that's more susceptible to everyday irritation.

— Anonymous, Allure, 23 July 2026

Definition of susceptible

Adjective

When giant hailstones start falling, or howling winter winds threaten to tear solar panels from the roof, the unprotected modules can do nothing but take the beating.

— Mrigakshi Dixit, Interesting Engineering, 17 July 2026
After 27 years of diplomacy, a doughnut hole of unprotected land along the Blue Ridge Parkway has finally been acquired by the Blue Ridge Conservancy in North Carolina.

— Mark Price, Charlotte Observer, 14 July 2026

Definition of unprotected

Browse Nearby Words

undefeated

undefended

undefiled

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“Undefended.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undefended. Accessed 25 Jul. 2026.

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Synonyms of undefended

adjective

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