undefended

adjective

ˌən-di-ˈfen-dəd How to pronounce undefended (audio)
Definition of undefendednext
as in vulnerable
lacking protection from danger or resistance against attack the cowardly soldiers fled, leaving the palace undefended

Synonyms & Similar Words

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Antonyms & Near Antonyms

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 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 Back then, America feared an armada of Soviet bombers laden with A-bombs barreling over the horizon, dodging our few anti-aircraft batteries, and dropping their deadly payloads on undefended American cities. — Barry Scott Zellen, Hartford Courant, 22 Jan. 2026 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 See All Example Sentences for undefended
Recent Examples of Synonyms for undefended
  1. vulnerable
  2. helpless
  3. susceptible
  4. unprotected
Adjective
  • His opposition to the measure in California could still leave him vulnerable to criticism from progressives in a national Democratic primary.
    — Los Angeles Times, Los Angeles Times, 8 July 2026
  • However, that is changing as the US Department of Defense seeks more robust, less vulnerable power systems for military satellites that are less hazardous than the older spacecraft powered by uranium and plutonium.
    — David Szondy July 07, New Atlas, 8 July 2026
Definition of vulnerable
Adjective
  • The leading interpretation is that Smilodon delivered a single precise bite to the throat or belly, severing something vital in a target that was already helpless.
    — Scott Travers, Forbes.com, 1 July 2026
  • Pele controls the ball in the penalty area with his thigh, flips it over the head of the defender and smashes it past a helpless Kalle Svensson.
    — Assistant Sports Editor, Los Angeles Times, 29 June 2026
Definition of helpless
Adjective
  • However, people with weakened immune systems or certain underlying health conditions may be more susceptible to infection.
    — Anthony Thompson, USA Today, 2 July 2026
  • Cooking Oils Cooking oils high in unsaturated fats, such as olive, walnut, and flaxseed oils, are among the pantry items most susceptible to heat damage.
    — Anne Wolf, Martha Stewart, 1 July 2026
Definition of susceptible
Adjective
  • The Lakers also gave Utah unprotected first-round picks in 2031 and 2033, plus first-round pick swaps in 2028 and 2030.
    — Sam Vecenie, New York Times, 2 July 2026
  • The Celtics, after failing to land Antetokounmpo, sent Brown to Philly for Paul George, an unprotected 2031 first-round pick, a 2028 pick/swap, and two second-round picks.
    — Bryan Toporek, Forbes.com, 2 July 2026
Definition of unprotected

Browse Nearby Words

undefeated
undefended
undefiled
See all Nearby Words

Cite this Entry

“Undefended.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undefended. Accessed 10 Jul. 2026.

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