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

Unlike wealthy nations with the reserves and infrastructure to buffer the crisis in the Strait of Hormuz, import-dependent economies are more vulnerable to immediate, cascading supply chain shocks.

— Sophia Saifi, CNN Money, 16 July 2026
Adopted by the Atlanta City Council this spring, the initiative offers a framework to hold the city accountable for protecting workers’ rights and address the needs of vulnerable populations, among other goals, during World Cup games.

— DeAsia Paige, AJC.com, 15 July 2026

Definition of vulnerable

Adjective

While he’s been fighting in Troy, his palace has been overrun by men who want to marry his faithful wife, Penelope (Anne Hathaway), and murder his helpless son, Telemachus (Tom Holland).

— Amy Nicholson, Los Angeles Times, 15 July 2026
The grandfather is seen running around a few trees, but the bison soon catches up and tosses the helpless visitor eight feet in the air.

— Suzanne Yeo, ABC News, 13 July 2026

Definition of helpless

Adjective

Each saw human nature as susceptible to corruption by base impulses and self-interest.

— Donovan Fifield, The Conversation, 16 July 2026
FODMAPs get fermented by colonic bacteria, producing gas and causing bloating and other gastrointestinal symptoms in susceptible individuals.

— Anna Giorgi, Verywell Health, 15 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 19 Jul. 2026.

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Synonyms of undefended

adjective

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