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Synonyms

indefensible

American  
[in-di-fen-suh-buhl] / ˌɪn dɪˈfɛn sə bəl /

adjective

  1. not justifiable; inexcusable.

    indefensible behavior.

  2. incapable of being protected or defended against attack.

    an indefensible town.

    Synonyms:
    unprotected, defenseless, vulnerable
  3. incapable of being defended against criticism or denial; untenable.

    indefensible argument.


indefensible British  
/ ˌɪndɪˈfɛnsəbəl /

adjective

  1. not justifiable or excusable

  2. capable of being disagreed with; untenable

  3. incapable of defence against attack

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of indefensible

First recorded in 1520–30; in- 3 + defensible

Explanation

Something that's indefensible is inexcusable — there's no way to justify it. It's indefensible to take candy from a baby, or to give candy TO a baby, for that matter. Indefensible behavior is just plain terrible, and it can't be explained away. It's indefensible, for example, or for one country to drop a bomb on innocent civilians in another country. Indefensible, "not able to be defended," comes from in-, "not," plus the Latin defendere and its sense of "allege in defense."

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In Chicago, where so many students are already missing school, it’s particularly indefensible.

From The Wall Street Journal • May 8, 2026

Rosenior described the performance as "indefensible" and "unacceptable" after facing angry chants from Chelsea's travelling supporters on the south coast.

From BBC • Apr. 22, 2026

"Any war fought without limits is incompatible with the law. It is indefensible, inhumane and devastating for entire populations."

From Barron's • Apr. 6, 2026

If she weren’t such an indefensible character, Bondi’s efforts to save her job would be sad.

From Salon • Apr. 3, 2026

The firm shunned those who came seeking a defense of indefensible behavior, which was common enough in the unprincipled corridors of the financial district.

From "Big Science" by Michael Hiltzik

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