undefined

English

Etymology

From un- +‎ defined.

Pronunciation

• Audio (US):

  (file)

Adjective

undefined (not comparable)

1. Lacking a definition or value.
   • 1992, Lia Matera, Prior Convictions, page 121:

     We slid into our office, past two women discussing the "X factor," an apparently undefined quality their firm felt they lacked.

2. (mathematics, computing) That does not have a meaning and is thus not assigned an interpretation.

   The result of division by zero is undefined.

Synonyms

• (lacking a definition or value): indefinite, undefinable; see also Thesaurus:indistinct or Thesaurus:vague

Antonyms

• defined

Derived terms

• undefined behavior

Translations

lacking definition or value

• Bulgarian: неопределе́н (bg) (neopredelén)
• Catalan: indefinit (ca)
• Chinese:

  Mandarin: 未定義 / 未定义 (wèidìngyì)

• Czech: nedefinovaný
• Finnish: määrittelemätön (fi), epämääräinen (fi)
• French: indéfini (fr)
• Italian: indefinito (it)
• Polish: niezdefiniowany, nieokreślony (pl)
• Portuguese: indefinido (pt)
• Romanian: nedefinit (ro)
• Russian: неопределённый (ru) (neopredeljónnyj)

mathematics: without interpretation

• Catalan: indefinit (ca)
• Finnish: määrittelemätön (fi)
• French: indéfini (fr)
• Romanian: nedefinit (ro)
• Russian: неопределённый (ru) (neopredeljónnyj)

The translations below need to be checked and inserted above into the appropriate translation tables. See instructions at Wiktionary:Entry layout § Translations.

Translations to be checked

Noun

undefined (plural undefineds)

1. (computing) An undefined value.
   • 1987, J. E. Lapin, Portable C and UNIX System Programming (Prentice-Hall Software Series), Englewood Cliffs, N.J.: Prentice-Hall, Inc., →ISBN, page 72:

     [Option:] · [PDP11:] F [BSD:] · [XE 2.3:] [1] [XE 3.0:] · [SIII:] · [COFF:] · [meaning:] make undefineds global

   • 1988, Pearl Brereton, editor, Software Engineering Environments, Chichester, West Sussex: Ellis Horwood Limited, →ISBN, page 230:

     Every operation is defined completely either by delivering a value of some type depending only on the types of its operands or by causing some defined exception; there are no ‘undefineds’ in Ten15.

   • 2017, Neos. Thanh, “Arrays”, in JavaScript Programming, →ISBN, page 36:

     The Array object has these commonly-used properties: • .length: the number of items including undefineds.