There are 413 fourteen-letter words containing 2A, S, T and U, https://www.bestwordlist.com/c/a/5/14letterwordswithaastu.htm
ABSQUATULATING ACCENTUALITIES ACCOUNTANTSHIP ACCULTURATIONS ACCURATENESSES
ACCUSTOMATIONS ACTINOBACILLUS ACTINOURANIUMS ACTUALISATIONS ACTUALIZATIONS
ADEQUATENESSES ADIATHERMANOUS ADMEASUREMENTS ADVANTAGEOUSLY AERENCHYMATOUS
AGGLUTINATIONS AGROINDUSTRIAL ALTRUISTICALLY AMARANTHACEOUS AMATEURISHNESS
AMPHIBLASTULAE ANARTHROUSNESS ANGIOSTOMATOUS ANGUSTIFOLIATE ANISODACTYLOUS
ANNUITISATIONS ANNUITIZATIONS ANTEPENULTIMAS ANTHRAQUINONES ANTHROPOPHAGUS
ANTIBARBARUSES ANTICOAGULANTS ANTICONVULSANT ANTIGUERRILLAS ANTIHOMOSEXUAL
ANTIHUMANISTIC ANTINUCLEARIST ANTIQUARIANISM ANTIQUATEDNESS ANTIQUITARIANS
ANTIRHEUMATICS ANTIRITUALISMS ANTISCRIPTURAL ANTONINIANUSES APPROPINQUATES
AQUACULTURISTS ARGUMENTATIONS ARMAMENTARIUMS ARTICULATENESS ARTIODACTYLOUS
ASSAULTIVENESS ASSUMABILITIES AUDIOCASSETTES AUDITABILITIES AUTHENTICATORS
AUTHORISATIONS AUTHORITARIANS AUTHORIZATIONS AUTOALLOGAMIES AUTOANTIBODIES
AUTOCATALYSING AUTOIONISATION AUTOMATICITIES AUTOMATISATION AUTORADIOGRAMS
AUTOSCHEDIASMS AUTOSCHEDIAZED AUTOSCHEDIAZES AVASCULARITIES AVERRUNCATIONS
AVUNCULARITIES BACCALAUREATES BIOACCUMULATES BIOACOUSTICIAN BIOAERONAUTICS
BRUTALISATIONS BRUTALIZATIONS BUREAUCRATESES BUREAUCRATISED BUREAUCRATISES
BUREAUCRATISMS BUREAUCRATISTS BUREAUCRATIZES CALAMITOUSNESS CALCULATEDNESS
CANTANKEROUSLY CARBURISATIONS CARBURIZATIONS CASUALISATIONS CASUALIZATIONS
CATECHUMENATES CAUTERISATIONS CAUTERIZATIONS CHATEAUBRIANDS CIRCUMSTANTIAL
CIRCUMVALLATES CLAUSTROPHILIA CLAUSTROPHOBIA COASTGUARDSMAN COASTGUARDSMEN
COMMUNAUTAIRES COMMUNITARIANS CONFABULATIONS CONGRATULATORS CONNATURALISED
CONNATURALISES CONNATURALIZES CONNATURALNESS CONSTABULARIES CONSUBSTANTIAL
COUNTERASSAULT COUNTERATTACKS CYCLANTHACEOUS DAUGHTERBOARDS DEAMBULATORIES
DECAPSULATIONS DECARBURATIONS DEGRANULATIONS DEHUMANISATION DENATURALISING
DESQUAMATORIES DIAMANTIFEROUS DISAMBIGUATING DISAMBIGUATION DISARTICULATED
DISARTICULATES DISARTICULATOR DISNATURALISED DISNATURALISES DISNATURALIZED
DISNATURALIZES DOCUMENTARIANS EDUCATIONALIST ENCAPSULATIONS ENTHUSIASTICAL
EQUATABILITIES EXCLAUSTRATION EXSANGUINATING EXSANGUINATION EXTRAFORANEOUS
FASCICULATIONS FATIGUABLENESS FEUDALISATIONS FEUDALIZATIONS FLUNITRAZEPAMS
FLUOROACETATES FRUITARIANISMS FUNAMBULATIONS FUNDAMENTALISM FUNDAMENTALIST
GALACTOPHOROUS GASTRODUODENAL GASTROVASCULAR GRANDDAUGHTERS GRATICULATIONS
HABITUALNESSES HAEMATOPHAGOUS HALLUCINATIONS HARUSPICATIONS HUMANISTICALLY
ICHTHYOSAURIAN ILLUSTRATIONAL IMMACULATENESS IMMUNOASSAYIST INACCURATENESS
INADEQUATENESS INARTICULACIES INCAPSULATIONS INTERJACULATES INTRACUTANEOUS
INTRANSMUTABLE JOURNALISATION MACRODACTYLOUS MACROMUTATIONS MALACOSTRACOUS
MALADJUSTMENTS MANUFACTURINGS MATRICULATIONS MELASTOMACEOUS MISARTICULATED
MISARTICULATES MISCALCULATING MISCALCULATION MISCALCULATORS MISCATALOGUING
MISEVALUATIONS MONOUNSATURATE MOUNTAINBOARDS MULLIGATAWNIES MULTIMEGAWATTS
MULTINATIONALS MULTIRACIALISM MUSICALISATION MUSICALIZATION MUTUALISATIONS
MUTUALIZATIONS NATURALISATION NEURASTHENIACS NEUROANATOMIES NEUROANATOMIST
NEUROBLASTOMAS NEUTRALISATION NONSPECTACULAR NUCLEARISATION NUMISMATICALLY
NUTRACEUTICALS NYCTAGINACEOUS OUTMANIPULATES OVERSATURATING OVERSATURATION
OVERVALUATIONS PACHYDACTYLOUS PACHYDERMATOUS PALAEOCURRENTS PANDICULATIONS
PANSEXUALITIES PARALINGUISTIC PARAMENSTRUUMS PARANTHROPUSES PARENCHYMATOUS
PARTICULARISED PARTICULARISER PARTICULARISES PARTICULARISMS PARTICULARISTS
PARTICULARIZES PARTICULARNESS PASTEURISATION PASTEURIZATION PAUPERISATIONS
PAUPERIZATIONS PENNATULACEOUS PENTADACTYLOUS PERAMBULATIONS PERSUADABILITY
PHARMACEUTISTS PHONAUTOGRAPHS PLATYCEPHALOUS PLEASURABILITY PLURALISATIONS
PLURALIZATIONS POLYUNSATURATE POPULARISATION PORTULACACEOUS POSTAMPUTATION
POSTGRADUATION POSTMENOPAUSAL PROTOLANGUAGES PSEUDAESTHESIA PURCHASABILITY
QUADRILATERALS QUADRILITERALS QUADRUMVIRATES QUADRUPLICATES QUAESTIONARIES
QUALIFICATIONS QUALIFICATIVES QUANTIVALENCES QUARTERMASTERS QUARTODECIMANS
QUASIPARTICLES RECALCULATIONS REGULARISATION REMANUFACTURES RESTAURANTEURS
RITUALISATIONS RITUALIZATIONS SALUTARINESSES SANGUIFICATION SATURABILITIES
SAUROPTERYGIAN SECULARISATION SECULARIZATION SEMIAUTOMATICS SENSUALISATION
SENSUALIZATION SEPTUAGENARIAN SEPTUAGENARIES SEXUALISATIONS SEXUALIZATIONS
SLANTENDICULAR SLANTINDICULAR SOLITUDINARIAN SOMNAMBULATING SOMNAMBULATION
SOMNAMBULATORS SOUTHEASTWARDS SPECTACULARITY SQUATTOCRACIES STRANGULATIONS
STRATICULATION SUBAGGREGATION SUBALLOCATIONS SUBALTERNATION SUBASSOCIATION
SUBPROLETARIAT SUBSATURATIONS SUBSTANTIALISE SUBSTANTIALISM SUBSTANTIALIST
SUBSTANTIALITY SUBSTANTIALIZE SUBSTANTIATING SUBSTANTIATION SUBSTANTIATIVE
SUBSTANTIATORS SUBSTANTIVALLY SUBTERRANEANLY SULFACETAMIDES SULFAMETHAZINE
SULFATHIAZOLES SULPHACETAMIDE SULPHATHIAZOLE SUMMARISATIONS SUMMARIZATIONS
SUOVETAURILIAS SUPERANNUATING SUPERANNUATION SUPERNATATIONS SUPERNATURALLY
SUPERSATURATED SUPERSATURATES SUPERTERRANEAN SUPPLANTATIONS SUPRASEGMENTAL
SUSTAINABILITY TABULARISATION TETRADACTYLOUS THAUMATOGENIES THAUMATOLOGIES
THAUMATURGISMS THAUMATURGISTS THAUMATURGUSES THYMELAEACEOUS TRADUCIANISTIC
TRANSCAUCASIAN TRANSCUTANEOUS TRANSDUCTIONAL TRANSEXUALISMS TRANSMUTATIONS
TRANSSEXUALISM TRANSSEXUALITY TRANSVALUATING TRANSVALUATION TRAUMATISATION
TRAUMATOLOGIES TRIANGULATIONS TURANGAWAEWAES TYRANNOSAURIDS ULTRAFILTRATES
ULTRAGLAMOROUS ULTRAHAZARDOUS ULTRAMARATHONS ULTRAMASCULINE ULTRAMILITANTS
ULTRAMONTANISM ULTRAMONTANIST ULTRAREALISTIC ULTRAROMANTICS ULTRAROYALISTS
ULTRASONICALLY ULTRAWIDEBANDS UNACCLIMATISED UNAMIABILITIES UNAPPROPRIATES
UNDERGRADUATES UNDERSATURATED UNDERSTANDABLE UNDERSTANDABLY UNICAMERALISTS
UNILATERALISMS UNILATERALISTS UNINHABITABLES UNIVERSITARIAN UNMATERIALISED
UNMETAPHYSICAL UNNATURALISING UNPLEASANTNESS UNPLEASANTRIES UNRESTRAINABLE
UNSALABILITIES UNSATISFACTION UNSATISFACTORY UNSECTARIANISM UNSTANDARDISED
UNSTANDARDIZED UNSYSTEMATICAL UNTAMEABLENESS UNTRANSFERABLE UNTRANSLATABLE
UNTRANSLATABLY UNTRANSMUTABLE URALITISATIONS URALITIZATIONS URANOGRAPHISTS
URBANISTICALLY UTILITARIANISE UTILITARIANISM VACUOLISATIONS VACUOLIZATIONS
VALETUDINARIES VERNACULARISTS VILLEGGIATURAS VIRTUALISATION VISUALISATIONS
VISUALIZATIONS VULCANISATIONS VULCANIZATIONS VULGARISATIONS VULGARIZATIONS
WELTANSCHAUUNG WHATABOUTERIES XANTHOMELANOUS