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

Synonyms & Similar Words

Relevance

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

Adjective

Brightly colored and casual beach attire is a no-fail way to get flagged as a vulnerable tourist while abroad.

— Amelia McBride, Travel + Leisure, 2 Sep. 2026
Supply chains and raw materials are vulnerable to extreme weather, while unpredictable temperatures can affect when consumers want to buy and wear products.

— Rhonda Richford, Footwear News, 2 Sep. 2026

Definition of vulnerable

Adjective

Y’know, the two living, breathing, helpless children forced to sit idle while their mother and (almost) step-father constantly and brazenly risk abandoning them.

— Richard Lawson, HollywoodReporter, 3 Sep. 2026
Muslims who are peace-loving and helpless also need a hand up.

— Sun Sentinel Editorial Board, Sun Sentinel, 24 Aug. 2026

Definition of helpless

Adjective

In the current setup, teams select players that other teams leave unprotected and then must carry that player on their big-league roster for a full year.

— Evan Drellich, New York Times, 28 Aug. 2026
Splitting the shot up decreases vaccination rates and leaves children unprotected over a longer period, experts say.

— Zac Anderson, USA Today, 24 Aug. 2026

Definition of unprotected

Browse Nearby Words

undefeated

undefended

undefiled

See all Nearby Words

Cite this Entry

Style

“Undefended.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/undefended. Accessed 5 Sep. 2026.

Copy Citation

Synonyms of undefended

adjective

Example Sentences

Browse Nearby Words

Cite this Entry

More from Merriam-Webster

Word of the Day

matriculate

Popular in Grammar & Usage

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

A List of Most Commonly Confused Words

Why do we use apostrophes to show possession?

Is it 'nerve-racking' or 'nerve-wracking'?

What's the difference between 'fascism' and 'socialism'?

Popular in Wordplay

The Longest Long Words List

Stay Woke

Ye Olde Nincompoop: Old-Fashioned Words for 'Stupid'

14 Phobias You Probably Haven't Heard Of

The Words of the Week - Sept. 4

Popular

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

The Longest Long Words List

Stay Woke

Games & Quizzes