There are 809 fourteen-letter words containing A, G, I, S and T, https://www.bestwordlist.com/c/a/5/14letterwordswithagist.htm
ABSQUATULATING ACUPUNCTURINGS ADMINISTRATING AEROBIOLOGISTS AESTHESIOGENIC
AESTHETICISING AESTHETICIZING AFFREIGHTMENTS AGGIORNAMENTOS AGGLOMERATIONS
AGGLUTINATIONS AGGRANDISEMENT AGGRESSIVITIES AGREEABILITIES AGRICULTURISTS
AGRIFOODSTUFFS AGROBIOLOGISTS AGROFORESTRIES AGROINDUSTRIAL AGROINDUSTRIES
AGROSTOLOGICAL AGROSTOLOGISTS AGROTERRORISMS AIRTIGHTNESSES ALLEGORISATION
ALMIGHTINESSES ANAESTHETISING ANAESTHETIZING ANAGRAMMATISED ANAGRAMMATISES
ANAGRAMMATISMS ANAGRAMMATISTS ANAGRAMMATIZES ANASTIGMATISMS ANATHEMATISING
ANESTHESIOLOGY ANGIOSARCOMATA ANGIOSTOMATOUS ANGLICISATIONS ANGLICIZATIONS
ANGUSTIFOLIATE ANTAGONISATION ANTHROPOGENIES ANTHROPOGONIES ANTHROPOLOGIES
ANTHROPOLOGIST ANTIAGGRESSION ANTICOAGULANTS ANTIESTROGENIC ANTIFOREIGNERS
ANTIGENICITIES ANTIGUERRILLAS ANTILOGARITHMS ANTIOESTROGENS ANTIPHLOGISTIC
ANYTHINGARIANS APOGEOTROPISMS APOPHLEGMATICS APOSTROPHISING APOSTROPHIZING
APOTHEGMATISED APOTHEGMATISES APOTHEGMATISTS APOTHEGMATIZES ARACHNOLOGISTS
ARCHAEOLOGISTS ARGUMENTATIONS ARTHROGRAPHIES ASSEVERATINGLY ASTIGMATICALLY
ASTROBIOLOGIES ASTROBIOLOGIST ASTROGEOLOGIES ASTROGEOLOGIST ASTROLOGICALLY
ASTRONAVIGATOR ATTITUDINISING AUTOALLOGAMIES AUTOCATALYSING AUTORADIOGRAMS
AUTOSUGGESTING AUTOSUGGESTION AUTOSUGGESTIVE BACKSCATTERING BACKSCRATCHING
BACTERIOLOGIES BACTERIOLOGIST BACTERIOPHAGES BIBLIOPHAGISTS BIGHEARTEDNESS
BILINGUALITIES BIOREGIONALIST BLACKSMITHINGS BLAMESTORMINGS BRAINSTORMINGS
BRANCHIOSTEGAL BREASTFEEDINGS CABINETMAKINGS CALIGINOSITIES CALLIGRAPHISTS
CAMPANOLOGISTS CANDLELIGHTERS CARCINOLOGISTS CARPETBAGGINGS CATEGORISATION
CENTRIFUGALISE CHALCOGRAPHIST CHARACTERISING CHARTOGRAPHIES CHIROGRAPHISTS
CHLORARGYRITES CHROMATOLOGIES CHROMATOLOGIST CINEMATOGRAPHS CIRCUMSTANCING
CLIMATOLOGISTS COGITATIVENESS COGNOMINATIONS COINVESTIGATOR COLLEGIALITIES
COMETOGRAPHIES COMPAGINATIONS CONFIGURATIONS CONFLAGRATIONS CONGENIALITIES
CONGENITALNESS CONGLUTINATORS CONSERVATISING CONSERVATIZING CONSIGNATORIES
CONTAGIOUSNESS CONTAINERISING CONTRAGESTIONS CONTRAGESTIVES COSMOGRAPHISTS
COTRANSFERRING COTRANSPORTING COUNTERSEALING COUNTERSHADING COUNTERSTATING
CREDENTIALINGS CROSSHATCHINGS CRYPTOGRAPHIES CRYPTOGRAPHIST CYBERSQUATTING
CYBERSTALKINGS DACTYLIOLOGIES DAUGHTERLINESS DECAPITALISING DECENTRALISING
DECOMPENSATING DECONSECRATING DEFENESTRATING DEGLUTINATIONS DEGRANULATIONS
DEMILITARISING DEMONETARISING DENATURALISING DEOXYGENATIONS DEPHLEGMATIONS
DEREGISTRATION DERMATOLOGISTS DEROGATORINESS DESEGREGATIONS DESOBLIGEANTES
DESTIGMATIZING DESULPHURATING DEUTERAGONISTS DEUTEROGAMISTS DIABETOLOGISTS
DIAGEOTROPISMS DIAGNOSABILITY DIAGNOSTICALLY DIAGNOSTICIANS DIALECTOLOGIES
DIALECTOLOGIST DIGITALISATION DIGNIFICATIONS DISACCREDITING DISACCUSTOMING
DISADVANTAGING DISAFFILIATING DISAFFORESTING DISAGGREGATING DISAGGREGATION
DISAGGREGATIVE DISAMBIGUATING DISAMBIGUATION DISARRANGEMENT DISASSOCIATING
DISAUTHORISING DISAUTHORIZING DISCORPORATING DISCOURAGEMENT DISCRIMINATING
DISENGAGEMENTS DISENTHRALLING DISFIGURATIONS DISINTEGRATING DISINTEGRATION
DISINTEGRATIVE DISINTEGRATORS DISINTHRALLING DISINTRICATING DISINVIGORATED
DISINVIGORATES DISOBLIGATIONS DISORIENTATING DISPARAGEMENTS DISPLEASANTING
DISPROPRIATING DISQUANTITYING DOGMATICALNESS DOGMATISATIONS DOGMATIZATIONS
DRAUGHTINESSES EARTHSHAKINGLY ECTYPOGRAPHIES EDITORIALISING EGALITARIANISM
EMIGRATIONISTS EMOTIONALISING EPIGRAMMATISED EPIGRAMMATISER EPIGRAMMATISES
EPIGRAMMATISMS EPIGRAMMATISTS EPIGRAMMATIZES EPISTOLOGRAPHY ERGASTOPLASMIC
ESCHATOLOGICAL ESCHATOLOGISTS ESSENTIALISING ESSENTIALIZING ESTROGENICALLY
EULOGISTICALLY EVANGELISATION EXACTINGNESSES EXASPERATINGLY EXSANGUINATING
EXSANGUINATION EXSANGUINITIES EXTINGUISHABLE EXTINGUISHANTS EXTRAVAGANCIES
EXTRAVAGATIONS FACTIONALISING FANTASTICATING FARSIGHTEDNESS FARTHINGSWORTH
FATIGABILITIES FATIGUABLENESS FEATHERWEIGHTS FERRIMAGNETISM FERROMAGNETISM
FICTIONALISING FIGURABILITIES FIGURATIVENESS FINGERBREADTHS FLABBERGASTING
FLAGELLANTISMS FLAGITIOUSNESS FORGEABILITIES FRACTOGRAPHIES FRAGMENTATIONS
FRANGIBILITIES GALACTOMETRIES GALACTOPOIESES GALACTOPOIESIS GALACTOSAEMIAS
GALACTOSAMINES GALACTOSIDASES GALLICISATIONS GALLICIZATIONS GALVANISATIONS
GALVANIZATIONS GALVANOMETRIES GALVANOPLASTIC GALVANOTROPISM GARNISHEEMENTS
GASTIGHTNESSES GASTROPLASTIES GASTROSCOPISTS GELATINISATION GELATINOUSNESS
GEMEINSCHAFTEN GENERALISATION GENERATIONISMS GENTLEMANLIEST GENTLEMANSHIPS
GEODYNAMICISTS GEOGNOSTICALLY GEOMETRISATION GEOPOLITICIANS GEOSTRATEGICAL
GEOSTRATEGISTS GERMANISATIONS GERMANIZATIONS GERONTOCRACIES GERONTOPHILIAS
GERONTOPHOBIAS GESTICULATIONS GHETTOISATIONS GHETTOIZATIONS GIGANTICNESSES
GIGANTOMACHIAS GIGANTOMACHIES GLADIATORSHIPS GLAMORISATIONS GLAMORIZATIONS
GLIOBLASTOMATA GLOBALISATIONS GLOBALIZATIONS GLORIFICATIONS GLYCOSYLATIONS
GLYPTOGRAPHIES GONADECTOMISED GONADOTROPHINS GRAMMATICASTER GRAMMATICISING
GRAMMATOLOGIES GRAMMATOLOGIST GRANDSTANDINGS GRANGERISATION GRANITISATIONS
GRANITIZATIONS GRANTSMANSHIPS GRAPHITISATION GRATICULATIONS GRATIFICATIONS
GRATUITOUSNESS GREISENISATION GREISENIZATION GYNAECOLOGISTS GYNAECOMASTIAS
GYNAECOMASTIES GYROMAGNETISMS GYROSTABILISER GYROSTABILIZER GYROSTATICALLY
HAEMATOGENESIS HAEMATOLOGISTS HAGIOGRAPHISTS HAIRSPLITTINGS HAMARTIOLOGIES
HATEMONGERINGS HEMAGGLUTININS HEPATICOLOGIES HEPATICOLOGIST HEPATOMEGALIES
HETEROGAMETIES HETEROGLOSSIAS HETEROGRAPHIES HIEROGRAMMATES HISTOGENICALLY
HISTOLOGICALLY HISTOPATHOLOGY HISTORIOGRAPHY HOMOGENISATION HYDROGENATIONS
HYDROMAGNETICS ICHTHYOPHAGIES ICHTHYOPHAGIST ICHTHYOPHAGOUS IGNITABILITIES
IGNORANTNESSES ILLEGALISATION ILLEGITIMACIES ILLOGICALITIES IMPIGNORATIONS
IMPOSTHUMATING INDIGENISATION INEGALITARIANS INGURGITATIONS INORGANISATION
INTANGIBLENESS INTEGRATIONIST INTELLIGENTSIA INTERDIGITATES INTERFEROGRAMS
INTERLAYERINGS INTERMARRIAGES INTERREGIONALS INTERROGATIONS INTERROGATIVES
INTERSEGMENTAL INTRANSIGEANCE INTRANSIGEANTS INTRANSIGENCES INTRANSIGENTLY
INTROGRESSANTS INVESTIGATIONS IRREGULARITIES ISOAGGLUTININS ISOGEOTHERMALS
JARGONISATIONS JARGONIZATIONS JINGOISTICALLY KINDERGARTNERS KINEMATOGRAPHS
LACTOGLOBULINS LARYNGECTOMIES LARYNGOLOGISTS LARYNGOSCOPIST LAUGHINGSTOCKS
LAUGHWORTHIEST LEGALISTICALLY LEGERDEMAINIST LEGISLATORSHIP LEGISLATRESSES
LEGITIMATENESS LEGITIMATISING LEGITIMISATION LETTERSPACINGS LEXICOGRAPHIST
LIGNIFICATIONS LIGNOSULFONATE LINGUISTICALLY LINGUISTICIANS LIPOGRAMMATISM
LIPOGRAMMATIST LOGNORMALITIES LYMPHANGITIDES LYMPHANGITISES LYSOGENISATION
LYSOGENIZATION MAGISTRALITIES MAGISTRATESHIP MAGNETISATIONS MAGNETIZATIONS
MAGNETOMETRIES MAGNETOSPHERIC MAGNETOSTATICS MAGNIFICATIONS MAINSTREAMINGS
MAINSTREETINGS MALARIOLOGISTS MALIMPRINTINGS MANAGERIALISTS MANUFACTURINGS
MARTYROLOGISTS MASTIGOPHORANS MASTIGOPHOROUS MATCHBOARDINGS MEGALOPOLITANS
METACOGNITIONS METACOMPUTINGS METAGRABOLISED METAGRABOLISES METAGRABOLIZES
METAGROBOLISED METAGROBOLISES METAGROBOLIZES METALINGUISTIC METAMORPHOSING
MICROGRAVITIES MISARRANGEMENT MISATTRIBUTING MISCALCULATING MISCATALOGUING
MISCEGENATIONS MISMANAGEMENTS MISOGYNISTICAL MISPUNCTUATING MISTRANSLATING
MITHRIDATISING MONGRELISATION MOUNTEBANKINGS MOUSETRAPPINGS MULLIGATAWNIES
MULTIMEGAWATTS MUTAGENICITIES MYSTAGOGICALLY NARRATOLOGISTS NARROWCASTINGS
NAVIGABILITIES NEGATIVENESSES NEGOTIATRESSES NEONATOLOGISTS NITROGELATINES
NOCTIVAGATIONS NONNEGOTIABLES NONREGULATIONS NONSEGREGATION NONSIGNIFICANT
NONVEGETARIANS NUGATORINESSES NYCTAGINACEOUS OBLIGATORINESS OBSTREPERATING
ODONATOLOGISTS ODONTOGRAPHIES OESOPHAGITISES OLFACTOLOGISTS ONOMATOLOGISTS
ONYCHOPHAGISTS OPISTHOGLOSSAL OPISTHOGRAPHIC OPPIGNERATIONS OPPIGNORATIONS
ORGANISABILITY ORGANISATIONAL ORGANOGRAPHIST ORTHODIAGONALS ORTHOGNATHISMS
ORTHOGONALISED ORTHOGONALISES ORTHOGONALIZES ORTHOGRAPHISTS OSMOREGULATION
OSTEOLOGICALLY OUTFANGTHIEVES OVERBREATHINGS OVERESTIMATING OVERHARVESTING
OVERSATURATING PAGANISTICALLY PALAEBIOLOGIST PALAEOGRAPHIST PALEOBIOLOGIST
PALEOECOLOGIST PALEOMAGNETISM PALEOMAGNETIST PALEONTOLOGIES PALEONTOLOGIST
PALEOZOOLOGIST PALINGENESISTS PANGRAMMATISTS PANTHEOLOGISTS PARAGRAMMATIST
PARALINGUISTIC PARAMAGNETISMS PARAMETERISING PARASITOLOGIES PARASITOLOGIST
PARCHMENTISING PARENTHESISING PARENTHESIZING PARLIAMENTINGS PATHOBIOLOGIES
PEPTIDOGLYCANS PEREGRINATIONS PERINATOLOGIES PERINATOLOGIST PHANTASMAGORIA
PHANTASMAGORIC PHARMACOLOGIST PHARYNGOLOGIST PHARYNGOTOMIES PHLEGMATICNESS
PHLOGISTICATED PHLOGISTICATES PHONOGRAPHISTS PHOTOGRAPHISTS PHRASEOLOGISTS
PICTORIALISING PIDGINISATIONS PIDGINIZATIONS PIEZOMAGNETISM PLACENTOLOGIES
PLAGIOTROPISMS PLANETOLOGISTS PLAYWRIGHTINGS PNEUMATOLOGIES PNEUMATOLOGIST
PNEUMOGASTRICS POLITICALISING POSTCOLLEGIATE POSTGANGLIONIC POSTGRADUATION
POSTSURGICALLY PRAGMATISATION PREDESIGNATING PREDESIGNATION PREDESIGNATORY
PREDESTINATING PREFIGURATIONS PREGNABILITIES PRESANCTIFYING PRIMATOLOGISTS
PROGESTATIONAL PROGNOSTICATED PROGNOSTICATES PROGNOSTICATOR PROPAGANDISTIC
PROSTAGLANDINS PUGILISTICALLY PYRAMIDOLOGIST RADIOBIOLOGIST RADIOTELEGRAMS
REAGGREGATIONS REBROADCASTING RECAPITALISING RECONSECRATING REESTABLISHING
REFRIGERATIONS REGIMENTATIONS REGISTRARSHIPS REGISTRATIONAL REGULARISATION
REGURGITATIONS REINTEGRATIONS REINTERROGATES REINVESTIGATED REINVESTIGATES
REINVIGORATORS REMILITARISING RENEGOTIATIONS REORGANISATION REOXYGENATIONS
REPRISTINATING REREGISTRATION RESEGREGATIONS RETRANSFERRING RETRANSFORMING
RETRANSMITTING RHEUMATOLOGIES RHEUMATOLOGIST RONTGENISATION RUGGEDISATIONS
RUGGEDIZATIONS SALVAGEABILITY SANGUIFICATION SAUROPTERYGIAN SCHIZOGNATHOUS
SCHOOLTEACHING SCINTIGRAPHIES SECTARIANISING SECTARIANIZING SECTIONALISING
SECTIONALIZING SEGREGATIONIST SEIGNIORALTIES SELENOGRAPHIST SEMASIOLOGISTS
SEPTUAGENARIAN SEPTUAGENARIES SERODIAGNOSTIC SERONEGATIVITY SEXTUPLICATING
SHADOWCASTINGS SHAPESHIFTINGS SHARPSHOOTINGS SIGNALISATIONS SIGNALIZATIONS
SIGNIFICATIONS SKATEBOARDINGS SOLIDUNGULATES SOMNAMBULATING SOPHISTICATING
SOTERIOLOGICAL SOVIETOLOGICAL SPAGHETTIFYING SPECTROGRAPHIC SPECTROLOGICAL
SPELAEOLOGISTS SPERMATOGENIES SPERMATOGONIAL SPERMATOGONIUM SPHAGNOLOGISTS
SPIRITUALISING SPIRITUALIZING SPONGIOBLASTIC STAGECOACHINGS STAGFLATIONARY
STEAMROLLERING STEAMTIGHTNESS STEEPLECHASING STEGANOGRAPHIC STEGOCEPHALIAN
STENOGRAPHICAL STENOGRAPHISTS STEPPARENTINGS STEREOGRAPHIES STEREOGRAPHING
STICKHANDLINGS STIGMATIFEROUS STIGMATISATION STIGMATIZATION STIGMATOPHILIA
STOMATOGASTRIC STOMATOLOGICAL STOMATOLOGISTS STRAIGHTJACKET STRAIGHTNESSES
STRANGULATIONS STRATIGRAPHERS STRATIGRAPHIES STRATIGRAPHIST STREETWALKINGS
STRIKEBREAKING STYLOGRAPHICAL SUBAGGREGATION SUBCATEGORISED SUBCATEGORISES
SUBCATEGORIZED SUBCATEGORIZES SUBCONTRACTING SUBGENERATIONS SUBINFEUDATING
SUBIRRIGATIONS SUBSTANTIATING SUFFRAGETTISMS SUFFUMIGATIONS SUMMERSAULTING
SUPERANNUATING SUPERELEVATING SUPEREROGATING SUPEREROGATION SUPEREROGATIVE
SUPERGRAVITIES SUPEROVULATING SUPPLICATINGLY SURROGATESHIPS SWEETHEARTINGS
SYCOPHANTISING SYCOPHANTIZING SYLLOGISATIONS SYLLOGIZATIONS SYMPTOMATISING
SYMPTOMATIZING SYNERGETICALLY TACHYGRAPHISTS TANGIBLENESSES TECHNICALISING
TECHNOGRAPHIES TELANGIECTASES TELANGIECTASIA TELANGIECTASIS TELECOTTAGINGS
TELEMARKETINGS TELEVANGELISMS TELEVANGELISTS TENDOVAGINITIS TERATOGENICIST
TERGIVERSATING TERGIVERSATION TERGIVERSATORS TERGIVERSATORY TETRASPORANGIA
THANATOLOGISTS THAUMATOGENIES THAUMATOLOGIES THAUMATURGISMS THAUMATURGISTS
THEOLOGISATION THERMOGRAPHIES THERMOSTATTING TRAGICALNESSES TRAINSPOTTINGS
TRANQUILLISING TRANSCENDINGLY TRANSGENDERISM TRANSGRESSIONS TRANSMIGRATING
TRANSMIGRATION TRANSMIGRATIVE TRANSMIGRATORS TRANSMIGRATORY TRANSMOGRIFIED
TRANSMOGRIFIES TRANSPLANTINGS TRANSPORTINGLY TRANSSHIPPINGS TRANSVALUATING
TRAUMATOLOGIES TRIANGULATIONS TRILINGUALISMS TROUBLEMAKINGS TSUTSUGAMUSHIS
TURBOCHARGINGS ULTRARELIGIOUS ULTRARIGHTISMS ULTRARIGHTISTS UNAPPETISINGLY
UNCHRISTIANING UNCONSECRATING UNDERPAINTINGS UNDERSTAFFINGS UNDERSTANDINGS
UNDERSTRAPPING UNHESITATINGLY UNILINGUALISTS UNNATURALISING UNSYMPATHISING
UNSYMPATHIZING UPSTANDINGNESS URANOGRAPHISTS UTEROGESTATION VEGETARIANISMS
VEGETATIVENESS VERBIGERATIONS VIGILANTNESSES VILLAGISATIONS VILLAGIZATIONS
VILLEGGIATURAS VOLCANOLOGISTS VULCANOLOGISTS VULGARISATIONS VULGARIZATIONS
VULVOVAGINITIS WATERBOARDINGS WATERFLOODINGS WATERPROOFINGS WATERTIGHTNESS
WOOLGATHERINGS XENODIAGNOSTIC ZOOPATHOLOGIES ZYGODACTYLISMS