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 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
  1. vulnerable
  2. helpless
  3. susceptible
  4. unprotected
Adjective
  • And while global child mortality data for 2025 won’t be available for several months, health officials are already bracing for a surge in deaths among the world’s youngest and most vulnerable.
    — ABC News, ABC News, 13 Aug. 2026
  • District leaders warned that the move could leave CPS vulnerable to midyear cuts if the money doesn’t materialize.
    — Kate Armanini, Chicago Tribune, 13 Aug. 2026
Definition of vulnerable
Adjective
  • The wartime mood among European and American intellectuals was hopeless, or, rather, in her estimation, helpless.
    — David Denby, New Yorker, 10 Aug. 2026
  • And the sport — players in uniform and executives in suits alike — all march toward the cliff in shackles of their own design, seemingly helpless to find a compromise.
    — Miami Herald, Miami Herald, 5 Aug. 2026
Definition of helpless
Adjective
  • The two phantoms were designed to be adult females, since previous research found that breasts and ovaries are especially susceptible to radiation damage.
    — Charles Q. Choi, Space.com, 12 Aug. 2026
  • Without claim-level review capabilities, employers remain susceptible to inaccurate reimbursements regardless of efficiencies achieved through administrative processes.
    — Bruce Roffe, Forbes.com, 12 Aug. 2026
Definition of susceptible
Adjective
  • Instead, experts say that upping the number of shots increases injection pain, leaves children unprotected longer and lowers overall vaccination rates.
    — Finch Walker, USA Today, 12 Aug. 2026
  • They were discontinued because the ACIP and the American Academy of Pediatrics held that separate shots would mean more needles, more appointments and children left unprotected for longer.
    — Jake Scott, The Conversation, 12 Aug. 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 15 Aug. 2026.

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