There are 580 thirteen-letter words containing 2A, G and T, https://www.bestwordlist.com/c/a/4/13letterwordswithaagt.htm
ABORIGINALITY ACCLIMATISING ACCLIMATIZING ACCOMMODATING ACCULTURATING
ACHROMATISING ACHROMATIZING ACQUITTANCING ADVANTAGEABLE AEROGENERATOR
AGALMATOLITES AGATHODAIMONS AGGIORNAMENTI AGGIORNAMENTO AGGLOMERATING
AGGLOMERATION AGGLOMERATIVE AGGLUTINATING AGGLUTINATION AGGLUTINATIVE
AGGRADATIONAL AGGRAVATINGLY AGGREGATENESS AGGREGATIONAL AGGREGATIVELY
AGONISTICALLY AGRANULOCYTES ALPHABETISING ALPHABETIZING ALTERNATINGLY
AMALGAMATIONS AMPHIGASTRIUM ANAGRAMMATISE ANAGRAMMATISM ANAGRAMMATIST
ANAGRAMMATIZE ANASTIGMATISM ANGELOLATRIES ANGIOPLASTIES ANGLICISATION
ANGLICIZATION ANIMADVERTING ANTAGONISABLE ANTAGONIZABLE ANTHROPOPHAGI
ANTHROPOPHAGY ANTIALIASINGS ANTIANDROGENS ANTICIGARETTE ANTICOAGULANT
ANTIGENICALLY ANTIGRAVITIES ANTIGUERRILLA ANTIHIJACKING ANTILOGARITHM
ANYTHINGARIAN AORTOGRAPHIES APLANOGAMETES APOPHLEGMATIC APOTHEGMATISE
APOTHEGMATIST APOTHEGMATIZE APPOGGIATURAS APPROPRIATING APPROXIMATING
ARACHNOLOGIST ARCHAEOLOGIST ARCHEGONIATES ARGUMENTATION ARGUMENTATIVE
ARPEGGIATIONS ARTERIALISING ARTERIALIZING ARTERIOGRAPHY ASSASSINATING
ASSEMBLAGISTS ASSIGNABILITY ASSUBJUGATING ASTACOLOGICAL ASTACOLOGISTS
AUGMENTATIONS AUGMENTATIVES AUTECOLOGICAL AUTOBIOGRAPHY AUTOGRAPHICAL
AUTOMAGICALLY AUTORADIOGRAM AVERRUNCATING BACKSTABBINGS BACKSTARTINGS
BACKSTRAIGHTS BACKTRACKINGS BACTERIOPHAGE BACTERIOPHAGY BANTAMWEIGHTS
BEAUMONTAGUES BRAGGARTLIEST BREATHALYSING BREATHALYZING BROADCASTINGS
CABINETMAKING CALCULATINGLY CALLIGRAPHIST CAMPANOLOGIST CAPTIVATINGLY
CARBONYLATING CARBOXYLATING CARPETBAGGERS CARPETBAGGERY CARPETBAGGING
CARTILAGINOUS CARTOGRAPHERS CARTOGRAPHIES CATALOGUISING CATALOGUIZING
CATEGOREMATIC CATEGORICALLY CATEGORIZABLE CATERWAULINGS CATHODOGRAPHS
CATHODOGRAPHY CHANGEABILITY CHARGEABILITY CHARTOGRAPHER CHARTOGRAPHIC
CHROMATOGRAMS CHROMATOGRAPH CINEMATOGRAPH CLIMATOGRAPHY COAGULABILITY
COASTGUARDMAN COASTGUARDMEN COLLABORATING COMANAGEMENTS COMPAGINATING
COMPAGINATION CONCATENATING CONFABULATING CONFLAGRATING CONFLAGRATION
CONFLAGRATIVE CONGRATULABLE CONGRATULANTS CONGRATULATED CONGRATULATES
CONGRATULATOR CONJUGATIONAL CONTAMINATING CONTRAFAGOTTI CONTRAFAGOTTO
DACTYLOGRAPHY DAMAGEABILITY DARRAIGNMENTS DAUGHTERBOARD DECAPSULATING
DECARBONATING DEDRAMATISING DEDRAMATIZING DEFLAGRATIONS DEGLACIATIONS
DEGRADABILITY DEGRANULATION DEPAUPERATING DERMATOGRAPHY DEVASTATINGLY
DIAGNOSTICIAN DIALOGISTICAL DIAMAGNETISMS DIAPHRAGMATIC DIAPHRAGMITIS
DIGLADIATIONS DISADVANTAGED DISADVANTAGES DISAGGREGATED DISAGGREGATES
DISAMBIGUATED DISAMBIGUATES DISGRADATIONS DISPARAGEMENT DOGMATISATION
DOGMATIZATION DRAGGLETAILED DRAMATURGICAL DRAMATURGISTS DRAUGHTBOARDS
DRAUGHTSWOMAN EMARGINATIONS ENCAPSULATING ENDAMAGEMENTS ENGRAFTATIONS
ENIGMATICALLY ENSANGUINATED EPIGRAMMATISE EPIGRAMMATISM EPIGRAMMATIST
EPIGRAMMATIZE ERGASTOPLASMS ERGATOCRACIES ETHNOGRAPHICA EUSPORANGIATE
EUTHANATISING EUTHANATIZING EVANGELISTARY EXAGGERATEDLY EXAGGERATIONS
EXPURGATORIAL EXSANGUINATED EXSANGUINATES EXTRAGALACTIC EXTRAPOLATING
EXTRAVAGANCES EXTRAVAGANTLY EXTRAVAGANZAS EXTRAVAGATING EXTRAVAGATION
EXTRAVASATING FARTHINGLANDS FASCINATINGLY FATIGABLENESS FLABBERGASTED
FLAGELLANTISM FLAGELLATIONS FRACTIONATING FRAGMENTARILY FRAGMENTATING
FRAGMENTATION FUNAMBULATING GALACTAGOGUES GALACTOMETERS GALACTORRHEAS
GALACTORRHOEA GALACTOSAEMIA GALACTOSAEMIC GALACTOSAMINE GALACTOSEMIAS
GALACTOSIDASE GALLANTNESSES GALLICISATION GALLICIZATION GALRAVITCHING
GALVANISATION GALVANIZATION GALVANOMETERS GALVANOMETRIC GALVANOPLASTY
GALVANOTROPIC GAMIFICATIONS GAMOGENETICAL GANGSTERLANDS GASIFICATIONS
GASTROLOGICAL GASTROMANCIES GASTRONOMICAL GASTRULATIONS GELATINATIONS
GENTIANACEOUS GEOSTATIONARY GEOTACTICALLY GERATOLOGICAL GERIATRICIANS
GERMANISATION GERMANIZATION GIGANTOMACHIA GLADIATORSHIP GLAMORISATION
GLAMORIZATION GLIOBLASTOMAS GLOBALISATION GLOBALIZATION GNATHONICALLY
GRADABILITIES GRADATIONALLY GRADUATESHIPS GRAMMATICALLY GRAMMATICISED
GRAMMATICISES GRAMMATICISMS GRAMMATICIZED GRAMMATICIZES GRANDDAUGHTER
GRANDFATHERED GRANDFATHERLY GRANDPARENTAL GRANDSTANDERS GRANDSTANDING
GRANITISATION GRANITIZATION GRANTSMANSHIP GRANULARITIES GRANULOMATOUS
GRAPHITISABLE GRAPHITIZABLE GRATICULATION GRATIFICATION GRAVIMETRICAL
GRAVITATIONAL GUBERNATORIAL GYMNASTICALLY GYNAECOCRATIC GYNAECOMASTIA
GYNECOMASTIAS HAEMANGIOMATA HAEMATOGENOUS HAEMATOLOGIES HAEMATOLOGIST
HAGIOGRAPHIST HALLUCINATING HALOGENATIONS HANGABILITIES HARDSTANDINGS
HARUSPICATING HEARTBREAKING HEMATOLOGICAL HEMATOPHAGOUS HIEROGRAMMATE
HIEROGRAMMATS IDEOGRAMMATIC IMAGINATIONAL IMAGINATIVELY IMAGISTICALLY
IMMIGRATIONAL IMPREGNATABLE INAUGURATIONS INCAPSULATING INCARCERATING
INCARDINATING INDEFATIGABLE INDEFATIGABLY INEGALITARIAN INELABORATING
INGRAFTATIONS INGRATIATIONS INSTAGRAMMING INSTANTIATING INTERCALATING
INTERGALACTIC INTERGLACIALS INTERGRANULAR INTERMARGINAL INTERMARRIAGE
INTRAGALACTIC INTRANSIGEANT INVAGINATIONS JARGONISATION JARGONIZATION
JUDGMATICALLY KINEMATOGRAPH LANDGRAVIATES LEGALISATIONS LEGALIZATIONS
LEGISLATORIAL LETHARGICALLY LIPOGRAMMATIC LOGARITHMICAL LOGOGRAMMATIC
MACHICOLATING MAGISTERIALLY MAGISTRATICAL MAGISTRATURES MAGNANIMITIES
MAGNETISATION MAGNETIZATION MAGNETOGRAPHS MAGNETOPAUSES MAGNETOSTATIC
MAGNIFICATION MAINSTREAMING MAINTENANCING MALACOLOGISTS MALARIOLOGIST
MANAGEABILITY MANAGERIALIST MANSLAUGHTERS MANUFACTURING MARGINALITIES
MASTIGOPHORAN MATCHBOARDING MATERIALISING MATERIALIZING MATHEMATISING
MATHEMATIZING MATRICULATING MEGAKARYOCYTE MEGALOBLASTIC MEGALOPOLITAN
METAGNATHISMS METAGRABOLISE METAGRABOLIZE METALANGUAGES METALLOGRAPHY
METALLURGICAL METASTASISING METASTASIZING METRORRHAGIAS MISALLOCATING
MISCATALOGING MISCATALOGUED MISCATALOGUES MISEVALUATING MISMANAGEMENT
MONOGRAMMATIC MULTIGRAVIDAE MULTIGRAVIDAS MULTIMEGAWATT MUTAGENICALLY
NAPHTHALISING NAPHTHALIZING NARRATOLOGIES NARRATOLOGIST NARROWCASTING
NATIONALISING NATIONALIZING NEMATOLOGICAL NIGHTWATCHMAN NOCTIVAGATION
NONMANAGEMENT NONVEGETARIAN NOSTALGICALLY NOTHINGARIANS OCTOGENARIANS
ORGANISATIONS ORGANIZATIONS ORGANOTHERAPY ORGIASTICALLY ORTHODIAGONAL
OUTBARGAINING PAGANISATIONS PAGANIZATIONS PAINSTAKINGLY PAINTBALLINGS
PALAEONTOLOGY PALEOMAGNETIC PANGRAMMATIST PANTOGRAPHERS PANTOGRAPHIES
PANTOPHAGISTS PARAGNATHISMS PARAGRAPHISTS PARAMAGNETISM PARAMETRISING
PARAMETRIZING PARASITOLOGIC PARLIAMENTING PARTICIPATING PATHOGRAPHIES
PATRILINEAGES PERAMBULATING PERMANGANATES PHANTASMAGORY PHONAUTOGRAPH
PHRAGMOPLASTS PLAGIOCLASTIC POSTGRADUATES POSTINAUGURAL POTAMOLOGICAL
PRAGMATICALLY PRAGMATICISMS PRAGMATICISTS PREAMBULATING PREVARICATING
PROGRADATIONS PROPAGABILITY PROPAGANDISTS PROPAGATIONAL PROSTAGLANDIN
PROTOGALAXIES PROTOLANGUAGE PURGATORIALLY PUTANGITANGIS QUARTERSAWING
RADIOTELEGRAM RATIOCINATING RATIONALISING RATIONALIZING REACCLIMATING
REACQUAINTING REAGGREGATING REAGGREGATION REARRANGEMENT RECALCULATING
RECALIBRATING RECATALOGUING RECTANGULARLY REINCARNATING REPAGINATIONS
RETRANSLATING REVACCINATING SANCTUARISING SANCTUARIZING SANDBLASTINGS
SANDPAINTINGS SAUROGNATHOUS SCAPEGOATINGS SCAPEGOATISMS SEGREGATIONAL
SHADOWCASTING SIGNALISATION SIGNALIZATION SKATEBOARDING SLAUGHTERABLE
SOMATOLOGICAL SPERMATOGONIA STAGECOACHING STAGECOACHMAN STAGECOACHMEN
STALAGMITICAL STALAGMOMETER STALAGMOMETRY STANDARDISING STANDARDIZING
STEGANOGRAPHS STEGANOGRAPHY STEGOSAURIANS STIGMATICALLY STRAIGHTAWAYS
STRAIGHTLACED STRANGULATING STRANGULATION STRAPHANGINGS STRATEGETICAL
STRATEGICALLY STRATIGRAPHER STRATIGRAPHIC SUBAGGREGATES SUBALLOCATING
SUBTRIANGULAR SYLLABICATING SYNALLAGMATIC SYNTAGMATITES TACHYGRAPHERS
TACHYGRAPHIES TACHYGRAPHIST TANGENTIALITY TANTALISINGLY TANTALIZINGLY
TELAUTOGRAPHY TELEGRAMMATIC TERATOLOGICAL THANATOGRAPHY THANATOLOGIES
THANATOLOGIST THAUMATURGICS THAUMATURGIES THAUMATURGISM THAUMATURGIST
TOPOGRAPHICAL TRAILBLAZINGS TRANSLOCATING TRANSMIGRANTS TRANSMIGRATED
TRANSMIGRATES TRANSMIGRATOR TRANSPLANTING TRIANGULARITY TRIANGULATELY
TRIANGULATING TRIANGULATION TURANGAWAEWAE TYPOGRAPHICAL UNACQUAINTING
UNCALCULATING UNDERGRADUATE UNEXAGGERATED UNGRAMMATICAL UNIMAGINATIVE
UNINAUGURATED UPGRADABILITY URANOGRAPHIST VACILLATINGLY VAGRANTNESSES
VEGETARIANISM VILLAGISATION VILLAGIZATION VILLEGGIATURA VULGARISATION
VULGARIZATION WAISTCOATINGS WASHINGTONIAS WATERBOARDING ZEUGMATICALLY