undefined meaning: definition, etymology and quotations

undefined

adj

Etymology From un- + defined.

Lacking a definition or value.

We slid into our office, past two women discussing the "X factor," an apparently undefined quality their firm felt they lacked.1992, Lia Matera, Prior Convictions, page 121:

Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences That does not have a meaning and is thus not assigned an interpretation.

The result of division by zero is undefined.

Synonyms: indefinite, undefinable, vague
Antonyms: defined
Derived terms: undefined behavior, undefinedly, undefinedness

undefined

noun

Etymology From un- + defined.

Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences An undefined value.

[Option:] · [PDP11:] F [BSD:] · [XE 2.3:] [1] [XE 3.0:] · [SIII:] · [COFF:] · [meaning:] make undefineds global1987, J. E. Lapin, Portable C and UNIX System Programming (Prentice-Hall Software Series), Englewood Cliffs, N.J.: Prentice-Hall, Inc., →ISBN, page 72:
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 Ten15.1988, Pearl Brereton, editor, Software Engineering Environments, Chichester, West Sussex: Ellis Horwood Limited, →ISBN, page 230:

1 more example

The Array object has these commonly-used properties: • .length: the number of items including undefineds.2017, Neos. Thanh, “Arrays”, in JavaScript Programming, →ISBN, page 36: