13-Letter Words Starting with U
There are 171 thirteen-letter words that start with U on Word.ws, from ubiquitinated to upperclassman. The most common are understanding, unfortunately, uncomfortable, undergraduate and unprecedented.
Meanings from Wiktionary. Not an official Scrabble, Words With Friends or Wordle word list.
All 171 thirteen-letter words that start with U
UB
- ubiquitinated25adj. Modified or degraded by the attachment of ubiquitin molecules.
UL
- ultramarathon18n. A running race over a distance longer than 42.195 km (26 miles 385...
- ultraportable17adj. Extremely portable.
- ultraviolence18n. Unnecessary, unprovoked (usually brutal) violence; violent acts simply...
UN
- unabbreviated21adj. Not abbreviated.
- unaccompanied22adj. Travelling without companions.
- unaccountable19adj. Inexplicable; unable to be accounted for or explained.
- unaccountably22adv. Not able to be explained logically. Without being accountable, or...
- unadulterated15adj. Pure; not mixed or adulterated with anything.
- unadventurous17adj. Not adventurous.
- unambiguously21adv. In a manner that is not ambiguous; leaving no doubt; clearly.
- unanticipated18adj. Not anticipated.
- unappreciated20adj. Not deemed to have any value, valueless, worthless, not appreciated.
- unarticulated16adj. Not expressed in words.
- unascertained16adj. Not ascertained; uncertain; undetermined; unknown.
- unassimilated16adj. Not assimilated.
- uncapitalized27adj. Not capitalized.
- uncategorized26adj. Not having been sorted into a category.
- unceremonious17adj. Not ceremonious.
- unchallenging20adj. Not challenging; easy to do.
- uncharismatic22adj. Not charismatic; lacking charisma.
- uncircumcised22adj. Not circumcised, intact.
- uncleanliness15n. The state of being unclean or dirty.
- uncollectible19adj. That cannot be collected.
- uncomfortable22adj. Not comfortable; causing discomfort.
- uncomfortably25adv. In an uncomfortable manner.
- uncompensated20adj. Not compensated; having no compensation.
- uncompetitive22adj. That does not involve competition; not competitive.
- uncomplaining20adj. Without complaint; patient and tolerant.
- uncomplicated22adj. Simple; not complicated; basic.
- uncompromised22adj. Not compromised.
- unconcernedly21adv. In an unconcerned manner.
- unconditional16adj. Absolute; without conditions, limitations, reservations or...
- unconditioned17adj. Without conditions; absolute.
- unconformable22adj. Not conformable.
- unconformably25adv. In an unconformable manner.
- unconquerable26adj. Not conquerable; indomitable.
- unconsciously20adv. In an unconscious manner; unknowingly.
- unconsecrated18adj. Not consecrated.
- unconstrained16adj. Not constrained.
- unconstructed18adj. Not (yet) constructed.
- unconsummated20adj. Not consummated.
- uncontactable19adj. Not contactable, not having a means by which contact can be made.
- uncontainable17adj. That cannot be contained.
- uncontentious15adj. Not contentious.
- uncontestable17adj. Not contestable.
- uncooperative20adj. Not cooperative.
- uncoordinated17adj. Having components that act independently of each other.
- uncorrectable19adj. Unable to be corrected.
- undeliverable19adj. Not able to be delivered.
- underachiever22n. One who underachieves, i.e. performs less well than expected.
- undercarriage17n. The supporting structural framework of a land vehicle (such as a car...
- underclassman18n. A freshman or sophomore in a high school or college or equivalent.
- underclothing20n. Clothing worn next to the skin; underwear.
- undereducated18adj. Insufficiently educated.
- underemployed22adj. Employed in a job that offers fewer work hours than desired.
- underequipped28adj. Lacking sufficient equipment.
- underestimate16v. To estimate too low; to perceive (someone or something) as having a...
- underexplored24adj. Not explored (either physically or intellectually) to the usual degree.
- underexposure23n. The condition of being underexposed.
- underfinanced20adj. Lacking sufficient financing.
- undergraduate16n. A student at a university who has not yet received a degree.
- underhandedly22adv. In an underhanded manner.
- undermountain16adj. Beneath a mountain.
- underpainting17n. An initial layer of paint, often monochromatic, applied to a ground as...
- underprepared19adj. Not adequately prepared.
- underpressure16n. Insufficient pressure; a marked drop in pressure.
- underreported17adj. Reported as smaller or lesser than reality.
- underspending18n. The spending of too little money.
- understaffing21n. The situation of having insufficient members of staff.
- understanding16n. The act of one that understands or comprehends; the mental process of...
- understrength18adj. Lacking in number (of a military unit, sport team, etc.).
- underutilized24adj. Insufficiently utilized.
- underwhelming23adj. Failing to interest; not as exciting as promised or expected.
- undisciplined19adj. Not subjected to discipline, control or correction; uncorrected.
- undistributed17adj. Not distributed.
- undiversified21adj. Not diversified.
- unembarrassed18adj. Not embarrassed.
- unembellished21adj. Plain, unadorned, or simple.
- unemotionally18adv. In an unemotional manner.
- unenforceable20adj. Unable to be enforced.
- unenlightened18adj. Not enlightened; ignorant in general or of some particular fact.
- unequivocally30adv. In a way that leaves no doubt; in an unequivocal or unambiguous manner...
- unestablished19adj. Not established.
- unexceptional24adj. Not exceptional.
- unexperienced25adj. Synonym of inexperienced.
- unexplainable24adj. That doesn't have a known or readily available explanation.
- unexplainably27adv. In a way or to an extent that cannot be explained.
- unfalsifiable21adj. Not able to be proven false, but not necessarily true.
- unfamiliarity21n. Lack of familiarity; ignorance or inexperience.
- unfashionable21adj. Not fashionable.
- unfashionably24adv. In an unfashionable manner.
- unflinchingly25adv. Without showing fear or indecision; resolutely.
- unforeseeable18adj. Incapable of being foreseen or anticipated.
- unforgettable19adj. Very difficult or impossible to forget.
- unforgettably22adv. In an unforgettable manner; very memorably.
- unforgiveness20n. Lack of forgiveness.
- unforthcoming24adj. Not forthcoming; laconic or uncooperative.
- unfortunately19adv. Happening through bad luck, or because of some unfortunate event.
- unfulfillable21adj. Not fulfillable.
- ungentlemanly19adj. Not gentlemanly; not adhering to the high moral standards expected of a...
- ungrammatical20adj. In violation of one or more of the rules and conventions of a language...
- unhealthiness19n. The state of being unhealthy.
- unilateralism15n. A tendency of nations to act on their own, or with only minimal...
- unilateralist13adj. Supporting or advocating unilateralism.
- unillustrated14adj. Not illustrated.
- unimaginative19adj. Not imaginative.
- unimpeachable24adj. Not able to be impeached or reproached.
- unimpeachably27adv. In an unimpeachable manner.
- unimplemented20adj. Not implemented; not put into operation/service.
- uninformative21adj. Lacking useful or interesting information.
- uninhabitable20adj. Not fit for people (or other living things) to live in; not able to be...
- uninitialized23adj. Not initialized.
- unintelligent14adj. Not intelligent.
- unintentional13adj. Inadvertent; unwitting.
- uninteresting14adj. Arousing little or no interest; boring or uneventful.
- uninterrupted16adj. Continuing with no interruption.
- unintimidated17adj. Not intimidated.
- unjustifiable25adj. That cannot be justified, excused or pardoned.
- unjustifiably28adv. In an unjustifiable manner.
- unknowability25n. The quality or state of being unknowable.
- unmentionable17adj. Too embarrassing or shocking to be discussed.
- unmeritorious15adj. Not meritorious; without merit.
- unnaturalness13n. The state of being unnatural.
- unnecessarily18adv. In an unnecessary way; not by necessity.
- unobtrusively21adv. In an unobtrusive manner; in a manner that is not noticeable or blatant.
- unoriginality17n. The property of lacking originality, repetitiveness, triteness...
- unpasteurized25adj. Not pasteurized.
- unprecedented19adj. Never before seen, done, or experienced; without precedent.
- unpredictable20adj. Unable to be predicted.
- unpredictably23adv. In an unpredictable way.
- unpresentable17adj. Not presentable.
- unpressurized25adj. Not pressurized.
- unpretentious15adj. Simple, humble, not pretentious, plain.
- unpreventable20adj. Not preventable.
- unproblematic21adj. Not problematic (presenting problems) or not controversial.
- unprogressive19adj. Not progressive; not contributing to progress.
- unpublishable22adj. Not suitable for publication.
- unputdownable21adj. Of a person, etc.: difficult or impossible to put down (in various...
- unqualifiedly29adv. In an unqualified manner.
- unquestioning23adj. Believing without question; having absolute loyalty.
- unrecoverable20adj. Not recoverable; that cannot be recovered.
- unrelentingly17adv. Of an undesirable event, unceasingly.
- unreliability18n. The quality of being unreliable.
- unremittingly19adv. In an unremitting manner.
- unrepentantly18adv. In an unrepentant way.
- unrepresented16adj. Not represented.
- unsalvageable19adj. That cannot be salvaged; not salvageable.
- unsatisfiable18adj. Not satisfiable. Unable to be satisfied.
- unselfishness19n. The state of being unselfish.
- unsentimental15adj. Not sentimental.
- unserviceable20adj. Unusable; of no use.
- unspecialized27adj. Having no speciality, or particular purpose.
- unspectacular19adj. Not spectacular.
- unsubstantial15adj. Insubstantial.
- unsubstituted16adj. Not substituted.
- unsuitability18n. The quality of being unsuitable.
- unsupportable19adj. Not able to be supported or endured.
- unsurpassable17adj. Not surpassable; unable to be surpassed.
- unsustainable15adj. Not sustainable.
- unsustainably18adv. In an unsustainable manner.
- unsymmetrical22adj. Not symmetrical.
- unsympathetic25adj. Not sympathetic; ill-disposed.
- unthreatening17adj. Not threatening.
- untraditional14adj. Not traditional; departing from tradition.
- untransformed19adj. Not transformed; free of any transformation.
- untrustworthy22adj. Not deserving of trust; unreliable.
- unwarrantable18adj. Not warrantable; indefensible; not vindicable; not justifiable.
- unwillingness17n. The property of being unwilling.
UP
- upgradability22n. Capability of being improved in functionality by the addition or...
- upperclassman21n. A junior or senior student in a school or college.
1,966 rare thirteen-letter words that start with U
- uberveillance
- ubidecarenone
- ubiquitinable
- ubiquitinized
- ubiquitylated
- ulcerogenesis
- ulnotrochlear
- ulotrichalean
- ultrabithorax
- ultracautious
- ultracellular
- ultracharming
- ultracolossal
- ultracritical
- ultracryotome
- ultracryotomy
- ultradelicate
- ultradepleted
- ultradespotic
- ultradetailed
- ultradiscreet
- ultradiscrete
- ultradistance
- ultradistinct
- ultradogmatic
- ultraeligible
- ultraelliptic
- ultrafabulous
- ultrafamiliar
- ultrafeminine
- ultrafiltered
- ultrafiltrate
- ultrafinitism
- ultrafinitist
- ultraflexible
- ultrafunction
- ultrahardness
- ultraharmonic
- ultraintimate
- ultrainvolved
- ultralocality
- ultraloyalist
- ultraluminous
- ultramagnetic
- ultramaternal
- ultramilitant
- ultramoderate
- ultramutation
- ultramylonite
- ultranational
- ultraorthodox
- ultraparallel
- ultraparanoid
- ultrapersonal
- ultraphysical
- ultraplankton
- ultrapotassic
- ultrapowerful
- ultraprofound
- ultrapurified
- ultrararefied
- ultrarational
- ultrarelaxing
- ultrareliable
- ultrarightism
- ultrarightist
- ultraromantic
- ultraroyalism
- ultraroyalist
- ultrasanguine
- ultrascaffold
- ultrasecurity
- ultrasimplify
- ultrasonicate
- ultrasonogram
- ultrasonology
- ultraspecific
- ultraspectral
- ultraspinning
- ultraspiracle
- ultrastrongly
- ultrasynaptic
- ultratalented
- ultratelluric
- ultrathinness
- ultratropical
- ultravigilant
- ultravirility
- ultravirtuous
- ultrawideband
- ultrazodiacal
- umbelliferone
- umbelliferous
- umbelliprenin
- umbonulomorph
- umbraculiform
- umbraticolous
- umbriferously
- unabashedness
- unabbreviable
- unabidingness
- unabolishable
- unaccelerated
- unaccentuated
- unaccessioned
- unacclimation
- unaccumulable
- unaccumulated
- unacknowledge
- unacquiescent
- unacquisitive
- unacquittable
- unacrimonious
- unactivatable
- unadaptedness
- unaddressable
- unadjudicated
- unadornedness
- unadulterable
- unadvancement
- unadventuring
- unadversarial
- unadvertising
- unadvisedness
- unaerodynamic
- unaerosolized
- unaesthetical
- unaffectioned
- unaffiliation
- unaffiliative
- unaffrontable
- unaggrandized
- unaggravating
- unalcoholized
- unalgebraical
- unalgorithmic
- unallegorical
- unalliterated
- unalteredness
- unalternating
- unalternative
- unamalgamable
- unamalgamated
- unambitiously
- unambivalence
- unameliorated
- unamenability
- unamiableness
- unamicability
- unamortizable
- unamplifiable
- unanalogously
- unangelically
- unanimitarian
- unanimousness
- unannihilable
- unannihilated
- unannouncedly
- unantagonized
- unanxiousness
- unapologizing
- unapostatized
- unapostolical
- unappealingly
- unapperceived
- unappointable
- unapportioned
- unappreciable
- unappreciably
- unapprehended
- unapprenticed
- unapproaching
- unappropriate
- unapprovingly
- unarbitrarily
- unarguability
- unarpeggiated
- unarraignable
- unarrangeable
- unarticulable
- unashamedness
- unassaultable
- unassertively
- unassibilated
- unassimilable
- unassimilably
- unassociation
- unassociative
- unassuageable
- unassuageably
- unassuredness
- unastonishing
- unatmospheric
- unattemptable
- unattentively
- unattractable
- unattributive
- unattunedness
- unaugmentable
- unauthentical
- unautographed
- unautomatable
- unaxiomatized
- unbalanceable
- unbalancement
- unbalustraded
- unbargainable
- unbarricadoed
- unbashfulness
- unbastardized
- unbearability
- unbeatability
- unbeautifully
- unbefittingly
- unbefriending
- unbeginningly
- unbeglamoured
- unbeguilingly
- unbeleaguered
- unbelievingly
- unbelligerent
- unbenchmarked
- unbendingness
- unbenefitable
- unbenevolence
- unbenignantly
- unbeseemingly
- unbesiegeable
- unbespattered
- unbesprinkled
- unbewildering
- unbioturbated
- unblackleaded
- unblacklisted
- unblackmailed
- unblameworthy
- unblanchingly
- unblasphemous
- unblemishable
- unblemishedly
- unblenchingly
- unblessedness
- unblindfolded
- unbookishness
- unboundedness
- unbountifully
- unbowdlerized
- unbrainwashed
- unbreakfasted
- unbreatheable
- unbridledness
- unbrilliantly
- unbroadcasted
- unbrotherlike
- unbutcherlike
- uncaffeinated
- uncalculating
- uncalumniated
- uncamouflaged
- uncamphorated
- uncancellable
- uncanonically
- uncapableness
- uncapacitated
- uncaparisoned
- uncapitulated
- uncaptivating
- uncaramelized
- uncarburetted
- uncarefulness
- uncaricatured
- uncarnivorous
- uncarpentered
- uncastellated
- uncastratable
- uncatabolized
- uncataclysmic
- uncategorical
- uncatholicity
- uncatholicize
- unceasingness
- uncelebrating
- uncelebration
- uncentralized
- uncentrifuged
- uncertainness
- uncertifiable
- unchangedness
- unchannelized
- unchaotically
- uncharactered
- unchartedness
- unchastisable
- unchauffeured
- uncherishable
- unchewability
- unchloridized
- unchlorinated
- unchondrified
- unchristianly
The first 300 are shown.
Questions about these words
- How many thirteen-letter words that start with U are there?
- Word.ws lists 171 thirteen-letter words that start with U, plus 1,966 rare ones.
- What are common thirteen-letter words that start with U?
- understanding, unfortunately, uncomfortable, undergraduate, unprecedented, underestimate, unpredictable and unconditional.
- Which of the thirteen-letter words that start with U has the highest letter score?
- unequivocally scores 30 points with the standard letter tile values.
Related word lists
Source and license
Word lists and meanings adapted from the Wiktionary entry of each word. Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws left out names, abbreviations, misspellings and offensive words, and ordered the most common words by how often they appear in English (wordfreq). Meanings from Wiktionary; this is not an official Scrabble, Words With Friends or Wordle word list. Wiktionary data of 2026-09-02.
Cite this page: “13-Letter Words Starting with U: 171 Words.” Word.ws, https://word.ws/words/13-letter/starting-with-u. Based on Wiktionary, CC BY-SA 4.0.