Đồng nghĩa của optional

Đồng nghĩa: elective, voluntary,

Trái nghĩa: compulsory,

voluntary discretionary volitional elective discretional unforced nonobligatory facultative permissive uncompelled noncompulsory unrestricted arbitrary open possible extra non-compulsory non-mandatory not required up to the individual no strings attached at one's discretion deliberate willful gratuitous autonomous spontaneous witting willed free unbidden intended intentional unconstrained chosen unasked wished elected opted independent unprescribed designful freely free-willed volunteer open to choice unpaid honorary nonmandatory flexible freewill uncoerced willing unprompted at one's call natural artless genuine effortless self-imposed electoral voting constituent selective not compulsory filled by election chosen by election passed by vote wilful purposive knowing unenforced purposeful planned set studied conscious calculated purposed controlled at your discretion with intent done on purpose premeditated considered designed aforethought preconceived wanton prepense pre-planned predetermined unsolicited thought out in advance prearranged advised volunteered off your own bat undemanded meant contemplated measured thoughtful weighed reasoned thought-out self-conscious express schemed on purpose thought out with forethought impulsive uncontrived unrequested uninvited predestined freewilled gratis contracted anticipated cognizant strategic reasoning rational reflective responsible accidentally on purpose mindful wary predesigned determined predeterminate meditative aware cut-and-dried cold-blooded meditated voluntarily preconcerted proposed without prompting of your own accord careful of one's own accord mannered studious feigned strained contrived well-considered forced affected laboured guarded artificial investigated thought-through thought-about examined overworked prepared reviewed plotted overdone labored gone into

unrequired redundant needless nonessential dispensable gratuitous inessential expendable useless unneeded superfluous unessential extraneous surplus excess irrelevant avoidable extrinsic futile accidental undesirable worthless uncritical noncompulsory causeless fortuitous casual haphazard wanton supererogatory chance exorbitant prodigal random lavish profuse additional uncalled-for beside the point unnecessary unwanted unimportant not required cosmetic non-essential peripheral unwarranted incidental not needed uncalled for extra excessive trivial unmerited pointless purposeless supplementary secondary ornamental minor not necessary not essential surplus to requirements disposable undesired replaceable wasted de trop subsidiary immaterial subordinate accessory no need improving non-medical beautifying of little account to no avail to no purpose more supplemental added further unjustified unwelcome inappropriate fresh undeserved unjust unprovoked leftover unjustifiable uninvited undue inexcusable unforgivable unfair indefensible supernumerary over and above add-on special insignificant inconsequential petty trifling inconsiderable superficial groundless meaningless unreasonable frivolous slight tangential negligible paltry of no account senseless nugatory foolish small impertinent immoderate minute not pertinent inordinate Mickey Mouse neither here nor there of no consequence spare inapposite unpardonable unproductive light inapplicable small-fry unused lightweight too much fiddling little foreign irrelative piddling not germane in excess picayune improper niggling of no moment unwarrantable disproportionate of no importance not to the point ungrounded unseemly without reason unconscionable without cause unbecoming bottomless blameworthy reprehensible remaining fruitless insubstantial unrelated unconnected shallow adventitious empty silly lesser puerile flighty inane inapt valueless frothy fatuous nickel-and-dime idle unsubstantial ineffectual small-time low-ranking left over piffling superfluent footling nothing not worth mentioning second-rate of no matter minuscule infinitesimal out of place off the subject purportless of no great concern skippable removable inexpiable marginal diffuse culpable unacceptable remiss censurable regrettable unworthy outmoded disused ill-advised wrong unsuitable indecorous left parenthetical external alien supervenient odd reserve without justification outrageous bush-league minor-league uncelebrated obscure smalltime inappreciable consumable collateral sacrificable usable going begging too many luxury deadwood residual over ancillary excess baggage illicit unlawful illegal by the by by the way background auxiliary by-the-way by-the-by needed like a hole in the head illegitimate able to be sacrificed inferior omissible less important aimless unavailing minimal of little consequence of little importance tinpot null dinky zero zilch zip twopenny-halfpenny shoestring indifferent criminal residuary absurd hopeless unprofitable nonsensical of less importance occasional waste superabundant pleonastic to spare inconsequent tiny in vain overflowing extravagant overmuch extreme abounding unasked immoral unethical detached disconnected inconsiderate related contributory contributing unfounded no great shakes not worth speaking of measly piddly pimping remote independent unassociated unapt disparate dissociated outside insane inapropos separate inappurtenant on your hands not applicable off base not pertaining to off the topic not connected off the point not related nothing to do with not connected with out of order peppercorn exiguous hollow baseless felonious lawless inadmissible no big deal matter of indifference a matter of indifference makes no difference impotent all the same nongermane no never mind without rhyme or reason ineffective de minimis not worth bothering about nominal no-account unreasoning indiscriminate brutish careless disliked unloved rejected dishonest evil wicked dishonorable intrusive shunned friendless forsaken dishonourable wrongful unsupportable assumed reasonless light-headed harebrained vain featherbrained light-minded ditzy giddy lightheaded goofy scatterbrained ditsy dizzy birdbrained yeasty uncherished nothing to do with it not to the purpose frilly lacking substance flippant unhelpful wide of the mark unpopular outcast uncared-for lighthearted empty-headed time-wasting without depth of no merit of no value annoying discarded uncared for more than enough

arbitrary random erratic chance capricious inconsistent discretionary haphazard hit-or-miss unreasonable whimsical subjective casual irrational motiveless personal unmotivated unpredictable wild aimless catch-as-catch-can desultory groundless helter-skelter illogical scattered slapdash stray unjustifiable unjustified unreasoned unsupported wanton discretional fanciful indiscriminate uninformed wilful approximate frivolous injudicious irresponsible offhand supercilious superficial unaccountable unscientific wayward judgemental willful judgmental unsystematic irregular unmethodical disorganized chaotic careless incidental disorganised accidental fluky undirected unthinking uncertain unexpected unplanned variable thoughtless orderless disorderly all over the place unselective unsettled slipshod messy fortuitous inconstant designless unstable unfocused unpremeditated fitful heedless contingent blind hit or miss sloppy without purpose coincidental inadvertent temperamental jumbled serendipitous volatile perfunctory impulsive disconnected changeable incalculable unforeseeable hit and miss lackadaisical mercurial willy-nilly chancy lucky unforeseen cursory fickle remiss vacillating flighty confused directionless all over the map fluctuating changeful fluid unsteady mutable loose unconsidered skittish slap-happy unguided hit-and-miss flakey reckless flickery occasional purposeless odd higgledy-piggledy fluke flaky bipolar unreliable scattershot all over the shop trial and error lost up and down blowing hot and cold up in the air without goal without direction baseless unwarranted unfounded shot-in-the-dark uncritical undiscriminating rambling indeterminate hitty-missy without a goal undiscerning undifferentiating hasty scrambled uncontrolled non-linear nonuniform frenzied disordered promiscuous entropic mixed up fractal stochastic muddled aleatory freak sketchy hurried negligent quicksilver spasmodic intermittent sporadic recklessly carelessly hurry-scurry hastily untidy last-minute lone single isolated unintended unanticipated unintentional irrepressible excitable wavering clumsy protean unlooked-for flukey unwitting kaleidoscopic moody slovenly thrown-together lax giddy active movable elastic labile off and on in disorder slack neglectful shambolic mobile undependable ad hoc lucky-dog thrown together ever-changing yo-yo luck out luck in unsure up-and-down shoddy nonchalant improvident iffy adventitious out of the blue dubious dicey unknowable doubtful spot undivinable undisciplined uneven unconcerned spontaneous unorganised sudden uncoordinated unorganized devil-may-care unconscious touchy in the balance touch and go any which way any old way freakish quirky ungovernable faddish vagarious crotchety

additional ancillary auxiliary secondary subsidiary bonus peripheral supporting accessorial accessory accompanying complementary extra subordinate supplemental supplementary supportive affixed appended contributory add-on on the side attendant second added attached concomitant related coincidental connected enclosed adjunct annexed sub roundabout adjuvant adjunctive appurtenant subservient tributary corresponding collateral associated joint concurrent associate fellow coexistent attending coexisting coincident with following

extramural additional external extracurricular vocational secondary supplementary subsidiary

spare relief reserve second additional auxiliary backup substitute supplementary alternative emergency extra fallback supernumerary surplus alternate ancillary another free fresh leftover replacement standby supererogatory back-up fall-back in reserve in store other secondary supplemental new added further subsidiary more farther supporting accessory increased complementary subordinate subservient temporary superfluous contributory fill-in stand-in top-up unused appurtenant adjuvant assistant abetting stopgap collateral makeshift peripheral second-string bonus one more over-and-above redundant support supportive accompanying deputy understudy accessorial add-on adjunct back up junior associate in addition lesser lower attendant younger minor inferior smaller lowly on the side sub youngest under less extraneous excess new-found lower-level dummy provisional improvised proxy quick-and-dirty make-do tentative surrogate temp rough-and-ready substitutive throwaway slapdash second-rate low-ranking second-class low-grade lower-ranking second-fiddle vice- less important sub- acting pinch-hitting caretaker short-term interim ad interim supply pro tempore transitional pro tem different intervening changeover expediential locum possible provisionary provisory cover helping representative adoptive foster impromptu depute aiding holding assisting adjutant delegated equivalent double assisting in rough and ready reciprocal correlative non-standard augmenting unimportant incidental inessential marginal tangential mean non-essential dinky dependent tributary minor-league insignificant small-fry small-time bush-league small subject trivial substract inconsiderable petty of little account

variant alternative different derived divergent modified adapted altered disparate mutant other revised aberrant deviant exceptional rogue abnormal differing irregular various varying unlike distinct diverse dissimilar unalike distinctive heterogeneous varied unequal contrasting manifold separate unrelated diversified mixed assorted miscellaneous sundry omnifarious motley variegated multifarious divers incongruous contrastive contrary conflicting individual distinguishable discrepant opposed contradictory opposite incompatible clashing all manner of discrete legion inconsistent unsimilar nonidentical distant mismatched at odds at variance numerous many polymorphic many-sided peculiar changing multitudinal several multitudinous populous changeable unconnected poles apart unassociated discordant antithetical non-identical multiform protean indiscriminate unique eclectic alternate discriminable inharmonious disproportionate contrasted polymorphous deviating dissonant like night and day not the same like chalk and cheese ill-matched distinguishing opposing otherwise independent unallied offbeat myriad irreconcilable not alike disagreeing ill-assorted unsuited uneven antagonistic incomparable incongruent particular disharmonious asymmetric off-balance lopsided unjust misallied one-sided inequitable unreconcilable streets apart single antithetic diverging as like as chalk and cheese another incommensurable unmistakable differentiable foreign contradistinctive contradistinct differential oppositional untypical unnatural off-key factious atypical anomalous factional an assortment of a mixture of a range of a number of a variety of out of keeping nothing like polar oppugnant in opposition not similar piebald patchwork wide-ranging raggle-taggle ragtag kitchen-sink magpie promiscuous weird antonymous mismated unfriendly irresoluble reluctant diametrically opposed hostile hateful mutually exclusive unattached composite mongrel multiplex jumbled mosaic mingled odd amalgamate conglomerate confused uncoupled unlinked far from far cry not capable of comparison isolated march to a different drummer impertinent nongermane irrelative inappropriate not kin not kindred not related colorful multifaceted varicolored exotic colourful many and various inconsonant adverse antipathetic counter repugnant unmixable disconsonant unharmonious antipodal reverse diametric specific antipodean unsuitable uncoordinated incoherent respective diametrical incommensurate paradoxical converse dissenting unbalanced precise alien out of line not in keeping out of sync out of step at loggerheads express special on the outs disconnected especial unequivalent dissentient inconformable anti inimical uncongenial quarreling contrarient quarrelling warring against in disagreement in conflict complementary shifting absurd unpredictable distorted unavailing inapropos rambling illogical inapt unbecoming extraneous unintelligible twisted bizarre improper fitful fantastic discriminatory antipathic bipolar discriminating discriminative distinguished contrariant unfavorable unfavourable sole detached discriminational separated characteristic proper categorical not so disunited diacritical sour note polar opposite not as such idiosyncratic frictional acrimonious ambiguous nullifying contradictive ornery counteractive con negating agin self-contradictory sui generis other than supposed at odds with on a sour note unmatched inconstant jarring unadapted remote removed fluctuating unidentical variable no go unsteady erratic unstable random unsymmetrical asymmetrical unrelated to obverse cross personal own relevant corresponding out of tune out of harmony at outs whale of difference competing inverse reversed inequal not uniform not matching contrapositive violative irrelevant to incompatible to incongruent with unequal to incomparable to inconsistent with immaterial to alien to hostile to incompatible with foreign to adverse to in conflict with opposed to unacceptable to contrary to antagonistic to conflicting with oppugnant to unusual for repugnant to inimical to at variance with flip-side facing enemy restrictive repelling battling exposing protesting denying confronting controverting defensive disputed crossing allergic objecting combating defending obstructive gainsaying disputing rival each singular appropriate one-to-one at cross-purposes up against

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