There are 783 fifteen-letter words containing A, C and 2S, https://www.bestwordlist.com/c/a/4/15letterwordswithacss.htm ABSORBEFACIENTS ABSTRACTIONISMS ABSTRACTIONISTS ACCEPTINGNESSES ACCESSARINESSES ACCESSIBILITIES ACCESSORINESSES ACCOMPLISHMENTS ACCOUNTABLENESS ACCOUNTANTSHIPS ACHONDROPLASIAS ACQUISITIVENESS ACRIMONIOUSNESS ACROPARESTHESIA ADDICTIVENESSES AERODYNAMICISTS AEROELASTICIANS AFFECTIVENESSES AGRANULOCYTOSES AGRANULOCYTOSIS ALCOHOLISATIONS ALLEGORICALNESS ANAMORPHOSCOPES ANCYLOSTOMIASES ANCYLOSTOMIASIS ANDROMONOECISMS ANFRACTUOSITIES ANTAPHRODISIACS ANTIALCOHOLISMS ANTICAPITALISMS ANTICAPITALISTS ANTICONVULSANTS ANTICONVULSIVES ANTIHISTAMINICS ANTIMONARCHISTS ANTINEOPLASTICS ANTINUCLEARISTS ANTIPHLOGISTICS ANTIRADICALISMS ANTISEPTICISING ANTISOCIALITIES ANTISYPHILITICS APOCALYPTICISMS APPRENTICESHIPS ARACHNOIDITISES ARCHAEOMETRISTS ARCHEOBOTANISTS ARCHPRIESTHOODS ARCHPRIESTSHIPS ASCLEPIADACEOUS ASSOCIABILITIES ASSOCIATIONISMS ASSOCIATIONISTS ASSOCIATIVITIES ASTRODYNAMICIST ASTROPHYSICALLY ASTROPHYSICISTS ATHEROSCLEROSES ATHEROSCLEROSIS ATROCIOUSNESSES AUDACIOUSNESSES AUTOSCHEDIASTIC BACKSCATTERINGS BACKSCRATCHINGS BACTERIOLOGISTS BAREFACEDNESSES BASIDIOMYCETOUS BIDIALECTALISMS BIOACOUSTICIANS BIOASTRONAUTICS BIOSTATISTICIAN BLOCKHEADEDNESS BRACHIOSAURUSES BRAINSICKNESSES BRAUNSCHWEIGERS CANISTERISATION CAPACIOUSNESSES CAPITALISATIONS CARAMELISATIONS CARCINOSARCOMAS CARNIVOROUSNESS CASTANOSPERMINE CASTRAMETATIONS CATECHUMENSHIPS CATEGORICALNESS CATEGORISATIONS CAUSATIVENESSES CAUSELESSNESSES CEASELESSNESSES CENSURABILITIES CENTENARIANISMS CENTRALISATIONS CENTRICALNESSES CENTRIFUGALISES CENTRIPETALISMS CHALCOGRAPHISTS CHANCELLORSHIPS CHANGEFULNESSES CHANNELISATIONS CHAPTALISATIONS CHARACTERISTICS CHEMOTHERAPISTS CHLORITISATIONS CHOLESTYRAMINES CHOLINESTERASES CHORDAMESODERMS CHROMATICNESSES CHROMATOLOGISTS CHROMATOSPHERES CINCHONISATIONS CIRCUMSTANTIALS CLAMOROUSNESSES CLANDESTINENESS CLANDESTINITIES CLASSICALNESSES CLASSIFICATIONS CLASSLESSNESSES CLAUSTROPHILIAS CLAUSTROPHOBIAS CLEARHEADEDNESS CLEAVABLENESSES CLEISTOGAMOUSLY COCHAIRMANSHIPS COESSENTIALNESS COINSTANTANEOUS COINVESTIGATORS COLDHEARTEDNESS COLONISATIONIST COLORABLENESSES COLORFASTNESSES COMBATIVENESSES COMFORTABLENESS COMMANDANTSHIPS COMMENDABLENESS COMMENSURATIONS COMMISSARYSHIPS COMMISSIONAIRES COMMONPLACENESS COMPACTEDNESSES COMPARATIVENESS COMPASSIONATELY COMPASSIONATING COMPLIANTNESSES COMPLICATEDNESS COMRADELINESSES CONCEIVABLENESS CONCEPTUALISERS CONCESSIONAIRES CONCESSIONARIES CONCESSIONNAIRE CONCRETISATIONS CONFESSIONALISM CONFESSIONALIST CONFESSIONARIES CONFORMABLENESS CONFUSABILITIES CONGEALABLENESS CONGENIALNESSES CONGRESSIONALLY CONJUGATENESSES CONQUERABLENESS CONSANGUINITIES CONSECRATEDNESS CONSENTANEITIES CONSENTANEOUSLY CONSERVATIONIST CONSERVATORIUMS CONSERVATORSHIP CONSIDERATENESS CONSIMILARITIES CONSPIRATRESSES CONSTITUTIONALS CONSUBSTANTIATE CONSULTANTSHIPS CONTESSERATIONS CONTESTABLENESS CONTINENTALISMS CONTINENTALISTS CONTINUALNESSES CONTRACTIVENESS CONTRAPOSITIONS CONTRAPOSITIVES CONTRARIOUSNESS CONVALESCENCIES CONVERSABLENESS CONVERSATIONISM CONVERSATIONIST CONVOCATIONISTS CONVULSIONARIES COOPERATIONISTS COOPERATIVENESS CORPORATENESSES CORPOREALNESSES CORPUSCULARIANS CORRELATIVENESS COSMOPOLITANISM COTRANSDUCTIONS COUNTERASSAULTS COUNTERMEASURES COUNTERSHADINGS CRAPULOUSNESSES CRASHWORTHINESS CRESTFALLENNESS CROSSOPTERYGIAN CRUCIVERBALISMS CRUCIVERBALISTS CRYPTAESTHESIAS CRYPTOGRAPHISTS CRYSTALISATIONS CRYSTALIZATIONS CRYSTALLINITIES CRYSTALLISATION CUSTOMARINESSES CYBERSQUATTINGS CYCLOOXYGENASES CYLINDRICALNESS CYTOTAXONOMISTS DEBAUCHEDNESSES DECASUALISATION DECHRISTIANISED DECHRISTIANISES DECHRISTIANIZES DECIMALISATIONS DECOLONISATIONS DECOLORISATIONS DECOMPENSATIONS DECONSECRATIONS DELOCALISATIONS DESACRALISATION DESPICABILITIES DIALECTOLOGISTS DICHROMATICISMS DICTATORIALNESS DIFFRACTIVENESS DISACCHARIDASES DISACCOMMODATES DISACKNOWLEDGES DISAFFECTEDNESS DISAPPLICATIONS DISARTICULATORS DISASSOCIATIONS DISCIPLINARIANS DISCIPLINARIUMS DISCOLOURATIONS DISCOMBOBERATES DISCOMBOBULATES DISCONSOLATIONS DISCONTINUANCES DISCOUNTENANCES DISCOURAGEMENTS DISCRIMINATIONS DISENCHANTMENTS DISENCUMBRANCES DISENFRANCHISED DISENFRANCHISES DISGRACEFULNESS DISINCARCERATES DISINCLINATIONS DISINCORPORATES DISINHERITANCES DISSATISFACTION DISSATISFACTORY DISSOCIABLENESS DODECASYLLABLES DOLICHOSAURUSES DYSLOGISTICALLY ECCLESIASTICISM ECCLESIOLATRIES ECCREMOCARPUSES ECLAIRCISSEMENT ECOCATASTROPHES EDUCATIONALISTS EFFECTUALNESSES EFFICACIOUSNESS ELECTROANALYSES ELECTROANALYSIS ELECTRODIALYSES ELECTRODIALYSIS EMBRACINGNESSES EMPIRICALNESSES EMULSIFICATIONS ENCYCLOPAEDISMS ENCYCLOPAEDISTS EPISCOPALIANISM EQUIVOCALNESSES ESEMPLASTICALLY ESOPHAGOSCOPIES ESTERIFICATIONS EVANGELICALISMS EVANGELICALNESS EVOCATIVENESSES EXACERBESCENCES EXCEPTIONALISMS EXCEPTIONALISTS EXCEPTIONALNESS EXCITABLENESSES EXCLAUSTRATIONS EXCUSABLENESSES EXECRABLENESSES FACETIOUSNESSES FANATICALNESSES FANATICISATIONS FANTASTICALNESS FANTASTICATIONS FEATHERSTITCHES FETISHISTICALLY FICTIONISATIONS FIDEICOMMISSARY FORENSICALITIES FRACTIOUSNESSES FUGACIOUSNESSES FURACIOUSNESSES GLOSSOGRAPHICAL GRACELESSNESSES GRAMMATICALNESS GRAMMATICASTERS GRAPHICALNESSES HARPSICHORDISTS HEARTSICKNESSES HEMOCHROMATOSES HEMOCHROMATOSIS HEPATICOLOGISTS HERESTHETICIANS HETEROSCEDASTIC HIERACOSPHINGES HIERACOSPHINXES HOMOCHROMATISMS HOMOSOCIALITIES HYDROCEPHALUSES HYPOCHONDRIASES HYPOCHONDRIASIS HYPOCHONDRIASMS HYPOCHONDRIASTS ICHTHYOPHAGISTS ICHTHYOSAURIANS ICHTHYOSAURUSES IDENTICALNESSES IDIOMATICALNESS IDIOMATICNESSES IDIOTICALNESSES ILLOGICALNESSES IMMEDICABLENESS IMPLICATIVENESS IMPRACTICALNESS IMPROVISATRICES INACCESSIBILITY INCANDESCENCIES INCAPABLENESSES INCAPACIOUSNESS INCESSANTNESSES INCREMENTALISMS INCREMENTALISTS INCURABLENESSES INEFFECTUALNESS INEXCUSABLENESS INFRASTRUCTURES INSCRIBABLENESS INSCRUTABLENESS INSIGNIFICANCES INSOCIABILITIES INTERACTIONISMS INTERACTIONISTS INTERSCHOLASTIC INTERSECTIONALS INTRACTABLENESS INTRANSIGEANCES INTRANSIGENCIES INTRICATENESSES INTRINSICALNESS IRASCIBLENESSES IRREVOCABLENESS ISMATICALNESSES ISOTHIOCYANATES KAFFEEKLATSCHES KARSTIFICATIONS LACTIFEROUSNESS LARYNGOSCOPISTS LEUCAEMOGENESES LEUCAEMOGENESIS LEXICALISATIONS LEXICOGRAPHISTS LICENTIATESHIPS LISSENCEPHALIES LISSENCEPHALOUS LUCRATIVENESSES MACADAMISATIONS MACROSTRUCTURES MAGNIFICENTNESS MALICIOUSNESSES MASCULINENESSES MASCULINISATION MASOCHISTICALLY MASTOIDECTOMIES MATCHLESSNESSES MATRIARCHALISMS MEDICALISATIONS MENISPERMACEOUS MERCENARINESSES MERCURIALNESSES MESATICEPHALIES MESATICEPHALOUS METACHROMATISMS METAFICTIONISTS METALINGUISTICS METAPHYSICISING MICROAGGRESSION MICROAGGRESSIVE MICROAGGRESSORS MICROPULSATIONS MICROSATELLITES MISACCEPTATIONS MISAPPLICATIONS MISCALCULATIONS MISCELLANARIANS MISCELLANEOUSLY MISCHARACTERISE MISCOMPUTATIONS MISCORRELATIONS MISGOVERNAUNCES MISPUNCTUATIONS MISTRANSCRIBING MISVOCALISATION MONOCHROMATISMS MONOSACCHARIDES MUCOSANGUINEOUS MULTIRACIALISMS MUSCULOSKELETAL MUSICALISATIONS MUSICALIZATIONS MUSICOTHERAPIES NARCOTERRORISMS NARCOTERRORISTS NECESSARIANISMS NECESSARINESSES NEOCOLONIALISMS NEOCOLONIALISTS NEOCONSERVATISM NONCHARISMATICS NONCONSENSUALLY NONELASTICITIES NONPSYCHIATRIST NONSENSICALNESS NONSIGNIFICANTS NONSPECTACULARS NUCLEARISATIONS OCCASIONALITIES OESOPHAGOSCOPES OMOPLATOSCOPIES OPHTHALMOSCOPES OPSONIFICATIONS ORACULOUSNESSES ORCHESOGRAPHIES OSCILLOGRAPHIES OSTEOARTHRITICS OVERCAPITALISES OVERCENTRALISES OVERCLASSIFYING OVERCOMPENSATES OVERSPECIALISED OVERSPECIALISES OVERSPECIALIZES OXIDOREDUCTASES PALEOECOLOGISTS PANTISOCRATISTS PARADOXICALNESS PARALINGUISTICS PARASITICALNESS PARTICULARISERS PASSIFLORACEOUS PATRIARCHALISMS PEACEABLENESSES PEACELESSNESSES PECTINESTERASES PENTADACTYLISMS PERIPATETICISMS PERISSODACTYLES PERISSODACTYLIC PERISSOSYLLABIC PERSPICACIOUSLY PESSIMISTICALLY PHALLOCENTRISMS PHARISAICALNESS PHARMACOGNOSIES PHARMACOGNOSIST PHARMACOLOGISTS PHARMACOPOEISTS PHARMACOPOLISTS PHARYNGOSCOPIES PHENAKISTOSCOPE PHOSPHOCREATINS PHOTODISSOCIATE PHYLLOSILICATES PICTORIALNESSES PINEALECTOMISES PLACELESSNESSES PLASTICISATIONS PLASTICIZATIONS POCOCURANTEISMS POLITICISATIONS POLYCHROMATISMS POLYSACCHARIDES POLYSACCHAROSES POLYSYLLABICISM POSTADOLESCENCE POSTADOLESCENTS POSTAPOCALYPSES POSTCONSONANTAL POSTSECONDARIES PRACTICABLENESS PRACTICALNESSES PRAGMATICALNESS PREADOLESCENCES PREANAESTHETICS PRECIPITANTNESS PRECIPITATENESS PREDICTABLENESS PREJUDICIALNESS PRINCIPALNESSES PROCELEUSMATICS PROCESSIONALIST PROCESSIONARIES PROCRASTINATORS PROCREATIVENESS PROCURATORSHIPS PROGNOSTICATORS PROJECTISATIONS PROSAICALNESSES PROSENCHYMATOUS PROSTATECTOMIES PROTOCERATOPSES PROVOCATIVENESS PSYCHOACOUSTICS PSYCHOANALYSERS PSYCHOANALYSING PSYCHOANALYZERS PSYCHOCHEMICALS PSYCHOHISTORIAN PSYCHOSEXUALITY PSYCHOTHERAPIES PSYCHOTHERAPIST PUNCTUATIONISTS PURITANICALNESS QUADRISYLLABICS QUATTROCENTISMS QUATTROCENTISTS RADICALISATIONS RANCOROUSNESSES RAPACIOUSNESSES REACTIONARYISMS RECANALISATIONS RECOLONISATIONS RECONDENSATIONS RECONNAISSANCES RECONNOISSANCES RECONSECRATIONS RECOVERABLENESS RECRYSTALLISING REPROACHFULNESS RESECTABILITIES RESINIFICATIONS RESOCIALISATION RESPECTABILISED RESPECTABILISES RESPECTABILIZES RESPECTABLENESS RETROACTIVENESS REVOCABLENESSES ROSTROCARINATES SABERMETRICIANS SACCHARIMETRIES SACCHARISATIONS SACCHARIZATIONS SACCHAROMETRIES SACCHAROMYCETES SACERDOTALISING SACRAMENTALISMS SACRAMENTALISTS SACRAMENTALNESS SACRAMENTARIANS SACROSANCTITIES SADOMASOCHISTIC SAGACIOUSNESSES SALACIOUSNESSES SALPINGECTOMIES SANCTIFICATIONS SANCTIMONIOUSLY SANGUIFICATIONS SANGUINOLENCIES SANSCULOTTERIES SAPONACEOUSNESS SAPONIFICATIONS SAPROGENICITIES SARCENCHYMATOUS SARRACENIACEOUS SATANICALNESSES SATIRICALNESSES SCANDALISATIONS SCANDALIZATIONS SCAPHOCEPHALICS SCAPHOCEPHALIES SCAPHOCEPHALISM SCAPHOCEPHALOUS SCAREMONGERINGS SCATHEFULNESSES SCEUOPHYLACIUMS SCHEMATISATIONS SCHEMATIZATIONS SCHILLERISATION SCHISTOSOMIASES SCHISTOSOMIASIS SCHOLARLINESSES SCHOOLMASTERING SCHOOLMASTERISH SCHOOLTEACHINGS SCINTILLASCOPES SCLERODERMATOUS SCLEROTHERAPIES SCLEROTISATIONS SCLEROTIZATIONS SCRATCHBUILDERS SCRIBACIOUSNESS SCRIMSHANDERING SEARCHABILITIES SEARCHINGNESSES SECONDARINESSES SECTIONISATIONS SECTIONIZATIONS SECULARISATIONS SECULARIZATIONS SECURITISATIONS SECURITIZATIONS SEISMOGRAPHICAL SEISMOLOGICALLY SEMIABSTRACTION SEMICENTENNIALS SEMICOLONIALISM SEMICRYSTALLINE SEMITRANSLUCENT SERICITISATIONS SERICITIZATIONS SEROPREVALENCES SERVICEABLENESS SERVOMECHANISMS SESQUICARBONATE SESQUICENTENARY SHOCKUMENTARIES SILICIFICATIONS SIMPLIFICATIONS SKEPTICALNESSES SKETCHABILITIES SOCIALISTICALLY SOCIOHISTORICAL SOLIDIFICATIONS SOLIPSISTICALLY SOPHISTICATEDLY SOPHISTICATIONS SPECIALISATIONS SPECIALIZATIONS SPECTROGRAPHIES SPECTROSCOPICAL SPECULATIVENESS SPERMATOBLASTIC SPHAEROCRYSTALS SPHERICALNESSES SPINTHARISCOPES SPIRONOLACTONES SPLANCHNOLOGIES STAPHYLOPLASTIC STEEPLECHASINGS STEGOCEPHALIANS STOCKBROKERAGES STRAIGHTJACKETS STRAITLACEDNESS STRAITWAISTCOAT STRATICULATIONS STRATIFICATIONS STRATOSPHERICAL STRATOVOLCANOES STREPTOBACILLUS STREPTOCARPUSES STRUCTURALISING STULTIFICATIONS SUBASSOCIATIONS SUBCATEGORISING SUBCIVILISATION SUBCONTRACTINGS SUBMETACENTRICS SUBSPECIALISING SUBSPECIALITIES SUBSPECIALIZING SUBSPECIFICALLY SUBVOCALISATION SULPHACETAMIDES SUPERABUNDANCES SUPERACTIVITIES SUPERCARGOSHIPS SUPERFICIALISED SUPERFICIALISES SUPERFICIALIZES SUPERFICIALNESS SUPERORGANICISM SUPERORGANICIST SUPERPLASTICITY SUPERSPECIALIST SUPERSPECTACLES SUPERSTRUCTURAL SUSPERCOLLATING SYLLOGISTICALLY SYMBOLISTICALLY SYMMETRICALNESS SYMPATHECTOMIES SYNCHRONISATION SYNCHRONISTICAL SYNCRETISATIONS SYNCRETIZATIONS SYNERGISTICALLY TEACHABLENESSES TECHNICALNESSES TELANGIECTASIAS TENACIOUSNESSES TERATOGENICISTS TETRABASICITIES THALASSOCRACIES THALASSOGRAPHIC THEOSOPHISTICAL THICKHEADEDNESS THORACOCENTESES THORACOCENTESIS THORACOPLASTIES TOUCHABLENESSES TRACEABLENESSES TRACKLESSNESSES TRACTABLENESSES TRANSCENDENCIES TRANSCENDENTALS TRANSHISTORICAL TRANSLUCIDITIES TRANSMITTANCIES TREACHEROUSNESS TRICHINISATIONS TRISOCTAHEDRONS ULTRAPRECISIONS ULTRASTRUCTURES UNCANONICALNESS UNCEASINGNESSES UNCERTAINNESSES UNCHRISTIANISED UNCHRISTIANISES UNCHRISTIANIZES UNCLEANLINESSES UNCLIMBABLENESS UNCOMBATIVENESS UNCOMPASSIONATE UNCONSENTANEOUS UNCREATEDNESSES UNEQUIVOCALNESS UNMUSICALNESSES UNNECESSARINESS UNPEACEABLENESS UNPRACTICALNESS UNPRACTISEDNESS UNSATISFACTIONS UNSECTARIANISMS UNSOCIABILITIES UNSOPHISTICATED UNTACTFULNESSES UNTEACHABLENESS UNTRACTABLENESS VASCULARISATION VASOCONSTRICTOR VERACIOUSNESSES VERTICILLASTERS VICARIOUSNESSES VICISSITUDINARY VINDICATIVENESS VISCOELASTICITY VISCOSIMETRICAL VIVACIOUSNESSES VORACIOUSNESSES WAPPENSCHAWINGS WATERCOLOURISTS WELTANSCHAUUNGS WHIMSICALNESSES