There are 423 fifteen-letter words containing A, 2I, R and U, https://www.bestwordlist.com/c/a/5/15letterwordswithaiiru.htm
ACQUIRABILITIES ACRIMONIOUSNESS AGRIBUSINESSMAN AGRIBUSINESSMEN
AGRICULTURALIST ALTITUDINARIANS ALUMINOTHERMIES ANFRACTUOSITIES
ANTIFILIBUSTERS ANTINUCLEARISTS ANTIQUARIANISMS ANTIREPUBLICANS
APPENDICULARIAN APPROPINQUATING APPROPINQUATION APPROPINQUITIES
ARBORICULTURIST ATRABILIOUSNESS ATTITUDINARIANS ATTRIBUTIVENESS
AUDIOMETRICALLY AUDIOMETRICIANS AUTHORITATIVELY AUTOBIOGRAPHIES
BIOASTRONAUTICS BUREAUCRATISING BUREAUCRATIZING CAPRIFOLIACEOUS
CENSURABILITIES CENTRIFUGALISED CENTRIFUGALISES CENTRIFUGALIZED
CENTRIFUGALIZES CENTRIFUGATIONS CIRCULARISATION CIRCULARIZATION
CIRCUMAMBAGIOUS CIRCUMAMBIENCES CIRCUMAMBIENTLY CIRCUMFERENTIAL
CIRCUMGYRATIONS CIRCUMJACENCIES CIRCUMNAVIGABLE CIRCUMNAVIGATED
CIRCUMNAVIGATES CIRCUMNAVIGATOR CIRCUMNUTATIONS CIRCUMSCRIBABLE
CIRCUMSTANTIALS CIRCUMSTANTIATE CIRCUMVALLATING CIRCUMVALLATION
CLAUSTROPHILIAS COLOURABILITIES COLOURISTICALLY COMPUTERISATION
COMPUTERIZATION CONFIGURATIONAL CONNATURALISING CONNATURALITIES
CONNATURALIZING CONVULSIONARIES COUNTERCLAIMING COUNTERINVASION
COUNTERIRRITANT COUNTERSTAINING CRUCIVERBALISMS CRUCIVERBALISTS
DECARBURISATION DECARBURIZATION DECOLOURISATION DECOLOURIZATION
DEINDUSTRIALISE DEINDUSTRIALIZE DEMISEMIQUAVERS DESPIRITUALISED
DESPIRITUALISES DESPIRITUALIZED DESPIRITUALIZES DESULFURISATION
DESULFURIZATION DISARTICULATING DISARTICULATION DISARTICULATORS
DISATTRIBUTIONS DISCIPLINARIUMS DISCOLOURATIONS DISEQUILIBRATED
DISEQUILIBRATES DISHARMONIOUSLY DISNATURALISING DISNATURALIZING
DISQUISITIONARY DISREPUTABILITY DOCUMENTARISING DOCUMENTARIZING
EBURNIFICATIONS EMPYREUMATISING EMPYREUMATIZING ENUMERABILITIES
EQUALITARIANISM EQUIPONDERATING EQUIPROBABILITY EUDIOMETRICALLY
EUTROPHICATIONS EXTRAJUDICIALLY EXTRALINGUISTIC EXTRUDABILITIES
FISSIPAROUSNESS FLIRTATIOUSNESS FORMULARISATION FORMULARIZATION
FRUCTIFICATIONS FUTILITARIANISM GRANULITISATION GRANULITIZATION
GUTTURALISATION GUTTURALIZATION HAEMOGLOBINURIA HAEMOGLOBINURIC
HEMOGLOBINURIAS HILARIOUSNESSES HONOURABILITIES HUMANITARIANISM
HUMANITARIANIST HYPERFASTIDIOUS HYPERMUTABILITY HYPERURICAEMIAS
HYPOPITUITARISM ICHTHYOSAURIANS IMMEASURABILITY IMMENSURABILITY
IMMUNOREACTIONS IMMUNOTHERAPIES IMPERTURBATIONS INARTICULATIONS
INDISTRIBUTABLE INDIVIDUALISERS INDIVIDUALIZERS INDUSTRIALISING
INDUSTRIALIZING INQUISITORIALLY INSTRUMENTALISM INSTRUMENTALIST
INSTRUMENTALITY INSTRUMENTATION INSUBORDINATELY INSUBORDINATION
INSURRECTIONARY INTERBEHAVIOURS INTERCLAVICULAR INTERFASCICULAR
INTERINDIVIDUAL INTERJACULATING INTERLACUSTRINE INTERMODULATION
INTEROSCULATING INTEROSCULATION INTERPOPULATION INTERSEXUALISMS
INTERTEXTUALITY INTRAFASCICULAR INTRAPOPULATION INTRAPRENEURIAL
INVOLUNTARINESS INVULNERABILITY JOURNALISATIONS JOURNALIZATIONS
JURISPRUDENTIAL LATITUDINARIANS MALDISTRIBUTION MANEUVERABILITY
MANOEUVRABILITY MARGARITIFEROUS MEASURABILITIES MENSURABILITIES
MICROPULSATIONS MICROSPORANGIUM MINIATURISATION MINIATURIZATION
MINICALCULATORS MISARTICULATING MISARTICULATION MISATTRIBUTIONS
MOUNTAINEERINGS MULTIARTICULATE MULTILATERALISM MULTILATERALIST
MULTIPOLARITIES MULTIRACIALISMS MULTITHREADINGS MUSICOTHERAPIES
NATURALISATIONS NATURALIZATIONS NEUROBIOLOGICAL NEUROFIBRILLARY
NEUROPLASTICITY NEUTRALISATIONS NEUTRALIZATIONS NONDURABILITIES
NONUTILITARIANS NUCLEARISATIONS NUCLEARIZATIONS NUDIBRANCHIATES
OMNIFARIOUSNESS OVERAMBITIOUSLY OVERCULTIVATION OVERSTIMULATING
OVERSTIMULATION OVERUTILISATION OVERUTILIZATION OVOVIVIPAROUSLY
PARALINGUISTICS PARASEXUALITIES PARTICULARISERS PARTICULARISING
PARTICULARISTIC PARTICULARITIES PARTICULARIZERS PARTICULARIZING
PARTURIFACIENTS PASTEURISATIONS PASTEURIZATIONS PENINSULARITIES
PERDURABILITIES PERMUTABILITIES PERSPICACIOUSLY PISCICULTURALLY
PLATITUDINARIAN PLATITUDINISERS PLATITUDINIZERS PLURALISTICALLY
POPULARISATIONS POPULARIZATIONS PREFIGURATIVELY PREJUDICIALNESS
PREPUBLICATIONS PRESSURISATIONS PRESSURIZATIONS PRONUNCIATIONAL
PRUDENTIALITIES PRUSSIANISATION PRUSSIANIZATION PSEUDEPIGRAPHIC
PURITANICALNESS QUADRINGENARIES QUADRIPARTITION QUADRISYLLABICS
QUADRIVALENCIES QUADRUPLICATING QUADRUPLICATION QUADRUPLICITIES
QUARTERFINALIST QUINALBARBITONE QUINCENTENARIES QUINGENTENARIES
QUINQUAGENARIAN QUODLIBETARIANS RADICULOPATHIES RADIOSTRONTIUMS
REARTICULATIONS REAUTHORISATION REAUTHORIZATION RECAPITULATIONS
RECONFIGURATION REDUPLICATIVELY REFUNDABILITIES REGULARISATIONS
REGULARIZATIONS REHUMANIZATIONS REINDUSTRIALISE REINDUSTRIALIZE
REPUBLICANISING REPUBLICANIZING REPUDIATIONISTS RESPIRITUALISED
RESPIRITUALISES RESPIRITUALIZED RESPIRITUALIZES RETURNABILITIES
REVISUALISATION REVISUALIZATION REVOLUTIONARIES REVOLUTIONARILY
RITUALISTICALLY ROUNDABOUTILITY RUDIMENTARINESS SCRATCHBUILDING
SCRIBACIOUSNESS SECULARISATIONS SECULARIZATIONS SECURITISATIONS
SECURITIZATIONS SILVICULTURALLY SINGULARISATION SINGULARIZATION
SOLITUDINARIANS SPIRITUALNESSES STRATICULATIONS STRUCTURALISING
STRUCTURALIZING SUBCATEGORISING SUBCATEGORIZING SUBLAPSARIANISM
SUBMINIATURISED SUBMINIATURISES SUBMINIATURIZED SUBMINIATURIZES
SUBORGANISATION SUBORGANIZATION SUBSTITUTIONARY SUBURBANISATION
SUBURBANIZATION SUBVERSIONARIES SULPHURISATIONS SULPHURIZATIONS
SUPERACTIVITIES SUPERADDITIONAL SUPERFICIALISED SUPERFICIALISES
SUPERFICIALIZED SUPERFICIALIZES SUPERFICIALNESS SUPERHUMANISING
SUPERHUMANITIES SUPERHUMANIZING SUPERINDIVIDUAL SUPERMAJORITIES
SUPERORDINATING SUPERORDINATION SUPERORGANICISM SUPERORGANICIST
SUPERPARASITISM SUPERPATRIOTISM SUPERPLASTICITY SUPERSPECIALIST
SURVIVABILITIES TABULARISATIONS TABULARIZATIONS THIOBARBITURATE
TRANQUILISATION TRANQUILISINGLY TRANQUILIZATION TRANQUILIZINGLY
TRANSEXUALITIES TRANSFIGURATION TRANSFUSIONISTS TRANSILLUMINATE
TRANSLUCIDITIES TRANSMUTABILITY TRAUMATISATIONS TRAUMATIZATIONS
TRIANGULARITIES TRIBUTARINESSES TRIFLUOPERAZINE TUBERCULISATION
TUBERCULIZATION UBIQUITARIANISM ULTRAFASTIDIOUS ULTRAFILTRATION
ULTRALIBERALISM ULTRAPRECISIONS ULTRAVIRILITIES UNANSWERABILITY
UNAPPRECIATIONS UNAPPROPRIATING UNAUTHORITATIVE UNCHRISTIANISED
UNCHRISTIANISES UNCHRISTIANIZED UNCHRISTIANIZES UNCHRISTIANLIKE
UNDERACTIVITIES UNDERCAPITALISE UNDERCAPITALIZE UNDERDIAGNOSING
UNDERESTIMATING UNDERESTIMATION UNDERINFLATIONS UNDETERMINATION
UNFAMILIARITIES UNIFORMITARIANS UNILATERALITIES UNINFORMATIVELY
UNIVERSALISABLE UNIVERSALIZABLE UNORIGINALITIES UNPATRIOTICALLY
UNPREMEDITATION UNPROFITABILITY UNREADABILITIES UNREALISTICALLY
UNRECONCILIABLE UNRELIABILITIES UNSECTARIANISMS UNSPIRITUALISED
UNSPIRITUALISES UNSPIRITUALIZED UNSPIRITUALIZES UNTRADITIONALLY
UNTRANSMISSIBLE UNVERIFIABILITY UNWORKABILITIES UPGRADABILITIES
UTILITARIANISED UTILITARIANISES UTILITARIANISMS UTILITARIANIZED
UTILITARIANIZES VALETUDINARIANS VAPOURABILITIES VASCULARISATION
VASCULARIZATION VENTRILOQUIALLY VERNACULARISING VERNACULARITIES
VERNACULARIZING VICARIOUSNESSES VICISSITUDINARY VIRTUALISATIONS
VIRTUALIZATIONS VOYEURISTICALLY VULNERABILITIES