GamesDaily CrosswordWord PuzzleWord FinderAll gamesFeaturedWord of the DayWord of the YearNew wordsLanguage storiesAll featuredCultureSlangEmojiMemesAcronymsGender and sexualityAll cultureWriting tipsWriting hubGrammar essentialsCommonly confusedAll writing tipsGamesFeaturedCultureWriting tipsAdvertisementSkip toSkip toundefinedadjective (2)AdvertisementView synonyms for AmericanBritishundefined[uhn-di-fahynd]Phonetic (Standard)IPAadjectivewithout 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.undefined/ ˌʌndɪˈfaɪnd /adjectivenot defined or made clearthe job has remained undefined“Collins English Dictionary — Complete & Unabridged” 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012Discover MoreOther Word Formsundefinable adjectiveundefinedly adverbundefinedness nounDiscover MoreWord History and OriginsOrigin of undefined1First recorded in 1605–15; + + Discover MoreExample SentencesExamples have not been reviewed.It was held, even in the South, to be a regrettable evil which the slave states would eventually abolish or allow to die out in some undefined way.From But experts say that this time, Mrs Trump will likely be more deliberate with her approach to the largely undefined role of being America’s First Lady.From The first rule allows county election officials to conduct a “reasonable inquiry” — an undefined term — before certifying the results of an election.From After the bid, a previously undefined range of food practices carried out by millions of people was reduced to a single meal which includes a serve of white rice with multiple side dishes.From The undefined “glitch” led to a drop in the electrical power that strips electrons from neutral xenon gas atoms and accelerates the resulting positive ions to produce thrust far more efficiently than chemical rockets.From AdvertisementDiscover MoreRelated Words AdvertisementAdvertisementAdvertisementBrowse#aabbccddeeffgghhiijjkkllmmnnooppqqrrssttuuvvwwxxyyzzContact usDo not sell my infoFollow usGet the Word of the Day every day!Sign upBy clicking "Sign Up", you are accepting Dictionary.com © 2025 Dictionary.com, LLC, The meaning of UNDEFINED is not defined. How to use undefined in a sentence., UNDEFINED definition: 1. not clearly described, stated, or known: 2. not having been given a definition (= a statement…. Learn more..