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Synonyms

undecided

American  
[uhn-di-sahy-did] / ˌʌn dɪˈsaɪ dɪd /

adjective

  1. not decided decided or determined.

  2. not having one's mind firmly made up.

    Synonyms:
    irresolute, vacillating, indecisive

noun

  1. a person who is undecided.

    Are you still among the undecideds?
undecided British  
/ ˌʌndɪˈsaɪdɪd /

adjective

  1. not having made up one's mind

  2. (of an issue, problem, etc) not agreed or decided upon

"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

  • undecidedly adverb
  • undecidedness noun

Etymology

Origin of undecided

First recorded in 1530–40; un- 1 + decided

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.

Allies say she remains undecided but is taking steps to preserve the option of a campaign.

From Barron's • Apr. 10, 2026

When asked about the captaincy in recent months, Woods has said he was undecided.

From BBC • Apr. 1, 2026

In the Emerson poll, more than 50% of voters were undecided on who to support for mayor.

From Los Angeles Times • Mar. 30, 2026

There were 1,678 responses to the final consultation, with 53% in favour, 14% offering at least conditional support, with 31% opposed and 3% undecided.

From BBC • Mar. 26, 2026

For a moment, I stared at him, undecided, repelled, not wanting to touch him again, let alone breathe into him.

From "Kindred" by Octavia Butler

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.