without fixed limits; indefinite in form, extent, or application: undefined authority; undefined feelings of sadness.
not given meaning or significance, as by a definition; not defined or explained: an undefined term.

Origin of undefined

1605–15; un-1 + defined
Related formsun·de·fin·ed·ly [uhn-di-fahy-nid-lee, -fahynd-] /ˌʌn dɪˈfaɪ nɪd li, -ˈfaɪnd-/, adverbun·de·fin·ed·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for undefined

Contemporary Examples of undefined

Historical Examples of undefined

  • With an undefined feeling of awe, she looked in the countenance of her friend.


    Lydia Maria Child

  • The position of the reputed slave in England was undefined and doubtful.


    Samuel Smiles

  • With its keen sensitive-ness and its undefined melancholy it was a dreamer's face.

  • The reason is that the negative proposition has really passed into an undefined positive.



  • Quaking with undefined fears, he pushed on until he had joined them.

    The Manxman

    Hall Caine

British Dictionary definitions for undefined



not defined or made clearthe job has remained undefined
Derived Formsundefinable, adjective
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

Word Origin and History for undefined

1610s, from un- (1) "not" + past participle of define (v.).

Online Etymology Dictionary, © 2010 Douglas Harper