undefined
English · Thesaurus
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undefined
adjective
-
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.
Similar: indefinite
- That does not have a logically sound meaning within a specific formal system and is thus not assigned an interpretation. The result of division by zero is undefined.
- That behaves unreliably due to dependence on an uninitialized value or inconsistently ported code. In C, relying on a variable's value right after a malloc call is undefined behvaior.
Similar: undefinable, vague · Opposite: defined
noun undefineds
- An undefined value. [Option:] · [PDP11:] F [BSD:] · [XE 2.3:] [1] [XE 3.0:] · [SIII:] · [COFF:] · [meaning:] make undefineds global
Thesaurus
Closest in meaning: indefinable, undefinable, vague, unspecified, unidentified, unknown, indeterminate, undetermined, unsorted, unallocated, open-ended, unlimited, imprecise, infinite, inaccurate, uncertain
adjective
Similar: undefinable, vague · Opposite: defined
Translations
Every language
adj lacking definition or value
| Español | indefinido |
|---|---|
| 中文 | 未定義 /未定义 wèidìngyì |
| Português | indefinido |
| Français | indéfini |
| Italiano | indefinito |
| Română | nedefinit |
| Русский | неопределённый neopredeljónnyj |
adj mathematics: without interpretation
| Français | indéfini |
|---|---|
| Română | nedefinit |
| Русский | неопределённый neopredeljónnyj |
| Tiếng Việt | không xác định |
Talk about this word "undefined." Wiktionary, via Micwyn, micwyn.com/word/undefined. Accessed 6 Nov. 2026. undefined. (n.d.). In Wiktionary, via Micwyn. Retrieved November 6, 2026, from https://micwyn.com/word/undefined "undefined." Wiktionary, via Micwyn. Accessed November 6, 2026. https://micwyn.com/word/undefined.Cite this
@misc{undefined_2026,
title = {undefined},
howpublished = {Wiktionary, via Micwyn},
year = {2026},
url = {https://micwyn.com/word/undefined},
urldate = {2026-11-06}
}
