undefined
Lacking clear boundaries
Undefined describes something that has not been given a definition, boundary, or value.
In mathematics and programming, undefined indicates a variable or expression that lacks an assigned value or produces no valid result: The function returns undefined when called without arguments.
More broadly, undefined describes anything vague or unspecified: The project timeline remains undefined.
Their relationship status is undefined.
Absence indicator in code
- NaNUnrepresentable numerical value
- uninitializedNot given initial value
- unassignedNot given out
- undeclaredNot officially acknowledged
variable · error · exception · placeholder · empty · void · nil · missing
Unclear, ill-defined
- ambiguousHaving multiple interpretations
- nebulousUnclear and formless
- indistinctUnclear, hard to perceive
- hazyUnclear, indistinct
fuzzy · blurry · murky · obscure · cloudy · muddled · imprecise · unspecified
Not yet complete
- partialFavoring one side
- fragmentaryConsisting of incomplete parts
- inchoatePartially formed, undeveloped
- undevelopedNot fully formed
sketchy · rudimentary · embryonic · nascent · immature · unrefined · rough · preliminary
Having no bounds
- limitlessWithout any boundaries
- unboundedHaving no limits
- endlessWithout termination or boundary
- unlimitedWithout bounds or restrictions
unrestricted · immeasurable · incalculable · unfixed · open-ended · unconstrained · unconfined · indeterminate
Beyond easy comprehension
- unexplainedNot yet clarified
- undiscoveredNot yet found
- unrevealedNot made public
- hiddenKept out of sight
concealed · secret · unexplored · uncharted · unfathomable · inscrutable · enigmatic · arcane
null
Absence indicator in code
- NaNUnrepresentable numerical value
- uninitializedNot given initial value
- unassignedNot given out
undeclared · variable · error · exception · placeholder · empty · void · nil · missing · default
vague
Unclear, ill-defined
- ambiguousHaving multiple interpretations
- nebulousUnclear and formless
- indistinctUnclear, hard to perceive
hazy · fuzzy · blurry · murky · obscure · cloudy · muddled · imprecise · unspecified · unclear
unfinished
Not yet complete
- partialFavoring one side
- fragmentaryConsisting of incomplete parts
- inchoatePartially formed, undeveloped
undeveloped · sketchy · rudimentary · embryonic · nascent · immature · unrefined · rough · preliminary · provisional
infinite
Having no bounds
unlimited · unrestricted · immeasurable · incalculable · unfixed · open-ended · unconstrained · unconfined · indeterminate · expansive
mysterious
Beyond easy comprehension
- unexplainedNot yet clarified
- undiscoveredNot yet found
- unrevealedNot made public
hidden · concealed · secret · unexplored · uncharted · unfathomable · inscrutable · enigmatic · arcane · esoteric
- debuggingdebug, debugging, debugger, breakpoint, breakpoints
- emptinessemptiness, void, vacuum, nothingness, blank
- unknownsmystery, enigma, puzzle, riddle, uncertain
- JavaScriptJavaScript, function, JS, variable, array
- parametersargument, help, verbose, version, parameter
- visionsharp, eye, visual perception, sight, eyes
undefineddefined
Given exact meaning
well-defined · specified · stated · established · clear
undefineddefined
Given exact meaning
initialized · assigned · determinate · set · computed
undefinedbounded
Confined within limits
limited · finite · circumscribed · delimited · demarcated