There are 770 twelve-letter words containing A, 2C and T, https://www.bestwordlist.com/c/a/4/12letterwordswithacct.htm
ACANTHACEOUS ACATALECTICS ACATALEPTICS ACCELERATING ACCELERATION
ACCELERATIVE ACCELERATORS ACCELERATORY ACCENTUALITY ACCENTUATING
ACCENTUATION ACCEPTANCIES ACCEPTATIONS ACCIACCATURA ACCIACCATURE
ACCIDENTALLY ACCIPITRINES ACCLAMATIONS ACCLIMATABLE ACCLIMATIONS
ACCLIMATISED ACCLIMATISER ACCLIMATISES ACCLIMATIZED ACCLIMATIZER
ACCLIMATIZES ACCOMMODATED ACCOMMODATES ACCOMMODATOR ACCOMPANISTS
ACCOMPANYIST ACCORDIONIST ACCOUCHEMENT ACCOUPLEMENT ACCOUTERMENT
ACCOUTREMENT ACCREDITABLE ACCRETIONARY ACCULTURATED ACCULTURATES
ACCUMULATING ACCUMULATION ACCUMULATIVE ACCUMULATORS ACCURATENESS
ACCUSATIVELY ACCUSATORIAL ACCUSTREMENT ACOUSTICALLY ACOUSTICIANS
ACQUAINTANCE ACQUIESCENTS ACQUITTANCED ACQUITTANCES ACROAMATICAL
ACROCENTRICS ACROPHONETIC ACROSTICALLY ACTINOMETRIC ACTINOMYCETE
ACTINOMYCINS ACUPUNCTURAL ACUPUNCTURES ALCOHOLICITY AMPHICTYONIC
ANACATHARTIC ANACREONTICS ANAPHYLACTIC ANAPTYCTICAL ANCHORETICAL
ANCHORITICAL ANDROCENTRIC ANTECEDENCES ANTIACADEMIC ANTIBACCHIUS
ANTICATHOLIC ANTICHOICERS ANTICLERICAL ANTICYCLONES ANTICYCLONIC
ANTIECONOMIC ANTIKICKBACK ANTIRACHITIC ANTISCIENCES APOCHROMATIC
APODEICTICAL APOPLECTICAL AQUACEUTICAL ARCHETYPICAL ARCHITECTING
ARCHITECTURE ARISTOCRATIC ARTHROSCOPIC ARTICULACIES ASCOMYCETOUS
ATTRACTANCES AUTOCEPHALIC AUTOCHTHONIC AUTOCORRECTS AUTOCRATICAL
AUTODIDACTIC BACKCHATTING BACKCOURTMAN BACKCOURTMEN BACKSCATTERS
BACKSTITCHED BACKSTITCHES BACKTRACKING BACTERICIDAL BACTERICIDES
BACTERIOCIDE BACTERIOCINS BATHOCHROMIC BESPECTACLED BIOACOUSTICS
BIOCATALYTIC BIOTECHNICAL BLACKCURRANT BLASTOCOELIC BRACHYDACTYL
BRECCIATIONS BUREAUCRATIC CABALISTICAL CABLECASTING CACHINNATING
CACHINNATION CACHINNATORY CACOTROPHIES CACTOBLASTES CACTOBLASTIS
CAENOGENETIC CAINOGENETIC CALCEAMENTUM CALCINATIONS CALCIPOTRIOL
CALCULATEDLY CALCULATIONS CALEFACIENTS CALEFACTIONS CALISTHENICS
CALLISTHENIC CALORICITIES CALORIMETRIC CALYCANTHEMY CANALICULATE
CANCELATIONS CANCELLATION CANCERATIONS CANDESCENTLY CANDLESTICKS
CANONICITIES CAPACITANCES CAPACITATING CAPACITATION CAPACITIVELY
CAPITALISTIC CAPROLACTAMS CAPTIVAUNCES CARDIOTONICS CARICATURING
CARICATURIST CARRIWITCHET CARTOGRAPHIC CARTOLOGICAL CARTOMANCIES
CARUNCULATED CATACAUSTICS CATACHRESTIC CATACOUSTICS CATADIOPTRIC
CATALLACTICS CATAPHORETIC CATAPHRACTIC CATAPHYSICAL CATASTROPHIC
CATCHINESSES CATCHPENNIES CATCHPHRASES CATECHESISES CATECHETICAL
CATECHISINGS CATECHIZINGS CATECHUMENAL CATHODICALLY CATHOLICALLY
CATHOLICATES CATHOLICISED CATHOLICISES CATHOLICISMS CATHOLICIZED
CATHOLICIZES CATHOLICOSES CATIONICALLY CAUSTICITIES CENTRALISTIC
CENTROCLINAL CENTUPLICATE CEROPLASTICS CERTIFICATED CERTIFICATES
CHALCANTHITE CHALCOLITHIC CHALCOPYRITE CHALICOTHERE CHANTICLEERS
CHARACTERFUL CHARACTERIES CHARACTERING CHARACTERISE CHARACTERISM
CHARACTERIZE CHARCOALIEST CHARCUTERIES CHARISMATICS CHATOYANCIES
CHAUVINISTIC CHELICERATES CHIROPRACTIC CHIROPRACTOR CHITCHATTING
CHLOROACETIC CHOCOLATIERS CHOCOLATIEST CHREMATISTIC CHROMATICISM
CHROMATICITY CHURCHIANITY CICATRICHULE CICATRICULAS CIRCULATABLE
CIRCULATINGS CIRCULATIONS CIRCUMGYRATE CIRCUMJACENT CIRCUMNUTATE
CIRCUMROTATE CIRCUMSTANCE CITIFICATION CITYFICATION CLADOGENETIC
CLASSICALIST CLASSICALITY CLASSICISTIC CLAUDICATION CLAVECINISTS
CLAVIERISTIC CLEARCUTTING CLEISTOGAMIC CLEPTOMANIAC CLERICALISTS
CLICKSTREAMS CLIMACTERICS CLIMATICALLY CLIMATOLOGIC CLIOMETRICAL
COACERVATING COACERVATION COACTIVITIES COADJUTRICES COARCTATIONS
COCAPTAINING COCCIDIOSTAT COCKAMAMIEST COCULTIVATED COCULTIVATES
CODIFICATION COEDUCATIONS COELACANTHIC COENOBITICAL COINCIDENTAL
COLLECTABLES COLLECTORATE COLLOCATIONS COLLUCTATION COLORCASTING
COLOURCASTED COMICALITIES COMMUNICANTS COMMUNICATED COMMUNICATEE
COMMUNICATES COMMUNICATOR COMPACTIFIED COMPACTIFIES COMPATRIOTIC
COMPLACENTLY COMPLICATING COMPLICATION COMPLICATIVE COMPORTANCES
CONCATENATED CONCATENATES CONCEALMENTS CONCELEBRANT CONCELEBRATE
CONCENTRATED CONCENTRATES CONCENTRATOR CONCENTRICAL CONCEPTACLES
CONCEPTIONAL CONCEPTUALLY CONCERTANTES CONCERTINAED CONCILIATING
CONCILIATION CONCILIATIVE CONCILIATORS CONCILIATORY CONCLAMATION
CONCOMITANCE CONCOMITANCY CONCOMITANTS CONCORDANTLY CONCORPORATE
CONCREMATION CONCUBITANCY CONCUBITANTS CONDUCTANCES CONDUCTIONAL
CONDUCTORIAL CONDUPLICATE CONFISCATING CONFISCATION CONFISCATORS
CONFISCATORY CONJUNCTIVAE CONJUNCTIVAL CONJUNCTIVAS CONJUNCTURAL
CONNECTIONAL CONSECRATING CONSECRATION CONSECRATIVE CONSECRATORS
CONSECRATORY CONSECTARIES CONSOCIATING CONSOCIATION CONSPIRACIST
CONTABESCENT CONTACTUALLY CONTINUANCES CONTRACTABLE CONTRACTABLY
CONTRACTEDLY CONTRACTIBLE CONTRACTIBLY CONTRACTIONS CONTRACTURAL
CONTRACTURES CONTRADANCES CONTRADICTED CONTRADICTER CONTRADICTOR
CONTRAOCTAVE CONTREDANCES CONTRIVANCES CONTUMACIOUS CONVALESCENT
CONVECTIONAL CONVICTIONAL CONVOCATIONS CORNSTARCHES CORRECTIONAL
CORTICATIONS CORUSCATIONS COSCENARISTS COSMETICALLY COSMETICIANS
COSMONAUTICS COSMOPLASTIC COSURFACTANT COTRANSDUCED COTRANSDUCES
COTTONOCRACY COUNTENANCED COUNTENANCER COUNTENANCES COUNTERACTED
COUNTERBRACE COUNTERCHARM COUNTERCLAIM COUNTERMARCH COUNTERPACES
COUNTERSCARP CRANIOMETRIC CRESCENTADES CRETACEOUSES CRETACEOUSLY
CRITICALNESS CRITICASTERS CRITICISABLE CRITICIZABLE CROSSHATCHED
CROSSHATCHES CROSSMATCHED CROSSMATCHES CROSSPATCHES CRYPTOCOCCAL
CRYSTALLITIC CUBISTICALLY CURVICAUDATE CURVICOSTATE CYANOGENETIC
CYBERATTACKS CYBERNETICAL CYCADOPHYTES CYCLANDELATE CYCLISATIONS
CYCLIZATIONS CYCLOPAEDIST CYCLOPENTANE CYCLOSTOMATE CYCLOTHYMIAC
CYCLOTHYMIAS CYTOCHALASIN CYTOCHEMICAL CZAREVITCHES DACTYLICALLY
DACTYLOSCOPY DECONSECRATE DECORTICATED DECORTICATES DECORTICATOR
DEFLOCCULANT DEFLOCCULATE DEMOCRATICAL DESICCATIONS DESICCATIVES
DESPOTOCRACY DIALECTICIAN DIALECTICISM DICHOTICALLY DICHROMATICS
DIDACTICALLY DIDACTICISMS DISACCORDANT DISACCREDITS DISACCUSTOMS
DISCALCEATES ECCLESIASTIC ECHOLOCATING ECHOLOCATION ECLECTICALLY
ECLIPTICALLY ECOTYPICALLY ECSTATICALLY EFFICACITIES EGOCENTRICAL
ELECTRICALLY ELECTRICIANS ELECTROCLASH ELECTRONICAS ENCEPHALITIC
ENCLITICALLY ENCROACHMENT ENDOCARDITIC ENTEROCOCCAL EPICUTICULAR
EPIDEICTICAL ESCHATOLOGIC EXCORTICATED EXCORTICATES EXCRUCIATING
EXCRUCIATION EXECUTANCIES EXORCISTICAL EXPECTANCIES EXSICCATIONS
FACTUALISTIC FASCICULATED FLACCIDITIES FLOCCULATING FLOCCULATION
FLOCCULATORS FRACTOCUMULI GALACTOSEMIC GASTROSCOPIC GEOCENTRICAL
GEOTECHNICAL GERONTOCRACY GNATCATCHERS GRANULOCYTIC GYNECOCRATIC
HECTOGRAPHIC HETEROCERCAL HETEROTACTIC HEXADACTYLIC HYGROCHASTIC
HYPOCRITICAL ICHTHYOCOLLA ICONOCLASTIC ICONOMACHIST INACCURATELY
INARTICULACY INCANDESCENT INCAPACITANT INCAPACITATE INCAPACITIES
INCARCERATED INCARCERATES INCARCERATOR INCULCATIONS INDOLEACETIC
INEFFICACITY INEXPECTANCY INOCCUPATION INSECTICIDAL INTERJACENCY
INTEROCEANIC INTERVOCALIC INTRACARDIAC INTRAPSYCHIC ISOCHROMATIC
KAKISTOCRACY KLEPTOCRATIC LACTESCENCES LACTOBACILLI LYCANTHROPIC
MACHICOLATED MACHICOLATES MACROBIOTICS MACROCLIMATE MACROCYTOSES
MACROCYTOSIS MACRODACTYLS MACRODACTYLY MALPRACTICES MARCASITICAL
MECHATRONICS MERITOCRATIC MESOTHORACIC METACENTRICS METACERCARIA
METAGALACTIC METAPSYCHICS METATHORACIC MICROCLIMATE MICROCRYSTAL
MICROPLASTIC MICROTOMICAL MISCALCULATE MISCHANCIEST MOBOCRATICAL
MOLECATCHERS MONARCHISTIC MOTORCOACHES MYCOBACTERIA NARCISSISTIC
NARCOLEPTICS NARCOTICALLY NECTOCALYCES NEMATOCYSTIC NONARCHITECT
NONCHARACTER NONCONTRACTS NONPRACTICAL NONTECHNICAL OCCIDENTALLY
OCCULTATIONS OCCUPATIONAL OCTASTICHONS OCTASTICHOUS OCTASTROPHIC
OCTOSYLLABIC OCTUPLICATES OLFACTRONICS OPHICALCITES OPTOACOUSTIC
ORGANICISTIC ORTHOCLASTIC OSTEOCLASTIC OSTEOMALACIC OVERCAPACITY
OVERCATCHING OVERCRITICAL PACIFICATING PACIFICATION PACIFICATORS
PACIFICATORY PANCHROMATIC PANTECHNICON PANTISOCRACY PARACROSTICS
PARATACTICAL PAROCCIPITAL PECTINACEOUS PEDANTOCRACY PENTARCHICAL
PERICARDITIC PERSPICACITY PHAGOCYTICAL PHAGOCYTOTIC PHALLOCRATIC
PHARMACEUTIC PHONOCAMPTIC PHONOTACTICS PHOTOACTINIC PHYLLOTACTIC
PHYSIOCRATIC PICTOGRAPHIC PICTORICALLY PINACOTHECAE PLUTOCRACIES
POCOCURANTES POSTACCIDENT POSTVACCINAL PRACTICALISM PRACTICALIST
PRACTICALITY PRECIPITANCE PRECIPITANCY PRECONTRACTS PREECLAMPTIC
PREOCCUPANTS PREOCCUPATED PREOCCUPATES PROPHYLACTIC PROSTACYCLIN
PSYCHOACTIVE PSYCHOPATHIC PUNDITOCRACY PYROCATECHIN PYROCATECHOL
PYROCLASTICS RACETRACKERS RADICALISTIC REACCELERATE REACCEPTANCE
REACCLIMATED REACCLIMATES REACCREDITED REACCUSTOMED RECALCITRANT
RECALCITRATE RECALCULATED RECALCULATES RECEPTACULAR RECEPTACULUM
RECIPROCANTS RECIPROCATED RECIPROCATES RECIPROCATOR RECIRCULATED
RECIRCULATES RECOMPACTING RECONSECRATE RECONTACTING REFLECTANCES
RELUCTANCIES REOCCUPATION REVACCINATED REVACCINATES SACCHARINITY
SACCULATIONS SACROCOSTALS SALTCHUCKERS SALTIMBOCCAS SANSCULOTTIC
SCARIFICATOR SCATOLOGICAL SCATTERMOUCH SCHECKLATONS SCHISMATICAL
SCHOLASTICAL SCHOOLCRAFTS SCIENTIFICAL SCRATCHBACKS SCRATCHBOARD
SCRATCHBUILD SCRATCHBUILT SCRATCHCARDS SCRATCHINESS SCRATCHINGLY
SCRATCHPLATE SCREENCRAFTS SCROBICULATE SECRETAGOGIC SECULARISTIC
SOLECISTICAL SPATCHCOCKED SPECIALISTIC SPECIFICATED SPECIFICATES
SPECTACULARS SPECTATRICES SPECULATRICE SPEECHCRAFTS SQUATTOCRACY
STAGECOACHES STAUROSCOPIC STEREOTACTIC STICKLEBACKS STITCHCRAFTS
STOMACHACHES STRATOCRATIC STYRACACEOUS SUBANTARCTIC SUBCLIMACTIC
SUBCONTRACTS SUBOCCIPITAL SUCCESSANTLY SUCCINCTORIA SUCCUSSATION
SUSCEPTANCES SWITCHBACKED SYNDIOTACTIC SYNECTICALLY SYNTACTICIAN
TACHEOMETRIC TACHYCARDIAC TACHYCARDIAS TACHYGRAPHIC TECHNICALISE
TECHNICALITY TECHNICALIZE TECHNOCRATIC TECHNOMANIAC TECTIBRANCHS
TECTONICALLY TELESCOPICAL TETRACYCLINE TETRARCHICAL TETRASTICHIC
THEOCRATICAL THERMOTACTIC THIGMOTACTIC THORACICALLY THORACOSCOPE
TICKTACKTOES TIMOCRATICAL TOBACCONISTS TRACHEOSCOPY TRAGICOMICAL
TRANSCALENCY TRANSLUCENCE TRANSLUCENCY TRANSOCEANIC TRANSPACIFIC
TRENCHANCIES TRICHROMATIC TROCHAICALLY TROCHANTERIC TROPHOTACTIC
ULTRACOMPACT UNACCEPTABLE UNACCEPTABLY UNACCEPTANCE UNACCLIMATED
UNACCREDITED UNACCUSTOMED UNCALCULATED UNCATCHABLES UNCIRCULATED
UNCOMPLACENT UNCONSECRATE UNCONTRACTED UNCRITICALLY UNDEMOCRATIC
UNSPECTACLED UNVACCINATED VACCINATIONS VISCOELASTIC VOCICULTURAL
WEATHERCOCKS XANTHOCHROIC ZOOTECHNICAL ZYGOCACTUSES ZYGODACTYLIC