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open-ended

[oh-puh n-en-did]
adjective
  1. not having fixed limits; unrestricted; broad: an open-ended discussion.
  2. allowing for future changes, revisions, or additions: open-ended agreements.
  3. having no fixed answer: an open-ended question.

Origin of open-ended

First recorded in 1815–25; open + end1 + -ed3
Related formso·pen-end·ed·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for openendedness

open-ended

adjective
  1. without definite limits, as of duration or amountan open-ended contract
  2. denoting a question, esp one on a questionnaire, that cannot be answered "yes", "no", or "don't know"
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 openendedness

open-ended

adj.

1825, from open (adj.) + end (n.).

Online Etymology Dictionary, © 2010 Douglas Harper