There are 414 fourteen-letter words containing A, G, P and T, https://www.bestwordlist.com/c/a/4/14letterwordswithagpt.htm
ACUPUNCTURINGS ANTHROPOGENIES ANTHROPOGONIES ANTHROPOGRAPHY ANTHROPOLOGIES
ANTHROPOLOGIST ANTHROPOPHAGIC ANTHROPOPHAGUS ANTIPHLOGISTIC APOGEOTROPISMS
APOLOGETICALLY APOPHLEGMATICS APOPHTHEGMATIC APOSTROPHISING APOSTROPHIZING
APOTHEGMATICAL APOTHEGMATISED APOTHEGMATISES APOTHEGMATISTS APOTHEGMATIZED
APOTHEGMATIZES APPROXIMEETING ARTERIOGRAPHIC ARTHROGRAPHIES AUTOBIOGRAPHER
AUTOBIOGRAPHIC AUTOCOPROPHAGY AUTORADIOGRAPH AUTOTYPOGRAPHY BACTERIOPHAGES
BACTERIOPHAGIC BATHYGRAPHICAL BIBLIOPHAGISTS CALLIGRAPHISTS CAMPANOLOGISTS
CARPETBAGGINGS CARTOGRAPHICAL CATHODOGRAPHER CENTUPLICATING CHALCOGRAPHIST
CHARTOGRAPHERS CHARTOGRAPHIES CHIROGRAPHISTS CHROMATOGRAPHS CHROMATOGRAPHY
CINEMATOGRAPHS CINEMATOGRAPHY COMETOGRAPHIES COMPAGINATIONS COMPARTMENTING
COMPURGATORIAL CONCORPORATING COSMOGRAPHISTS COTRANSPORTING COUNTERPLAYING
CRYPTOGRAPHERS CRYPTOGRAPHIES CRYPTOGRAPHIST CYTOPATHOGENIC DACTYLIOGRAPHY
DACTYLOGRAPHER DACTYLOGRAPHIC DAGUERREOTYPED DAGUERREOTYPER DAGUERREOTYPES
DECAPITALISING DECAPITALIZING DECOMPENSATING DEPHLEGMATIONS DEPIGMENTATION
DEPRECIATINGLY DERMATOGLYPHIC DERMATOGRAPHIA DERMATOGRAPHIC DESULPHURATING
DIAGEOTROPISMS DISCORPORATING DISPARAGEMENTS DISPLEASANTING DISPROPRIATING
DRAUGHTPROOFED DRAUGHTSPERSON ECTYPOGRAPHIES ELECTROGRAPHIC ELECTROPLATING
ENCEPHALITOGEN ENIGMATOGRAPHY EPEXEGETICALLY EPIGENETICALLY EPIGRAMMATICAL
EPIGRAMMATISED EPIGRAMMATISER EPIGRAMMATISES EPIGRAMMATISMS EPIGRAMMATISTS
EPIGRAMMATIZED EPIGRAMMATIZER EPIGRAMMATIZES EPISTOLOGRAPHY ERGASTOPLASMIC
ETHNOGRAPHICAL EXASPERATINGLY FRACTOGRAPHIES GALACTOPHOROUS GALACTOPOIESES
GALACTOPOIESIS GALACTOPOIETIC GALEOPITHECINE GALEOPITHECOID GALVANOPLASTIC
GALVANOTROPISM GASTROPLASTIES GASTROSCOPISTS GENTLEMANSHIPS GEOPOLITICALLY
GEOPOLITICIANS GERONTOPHILIAS GERONTOPHOBIAS GLADIATORSHIPS GLYPTOGRAPHERS
GLYPTOGRAPHIES GONADOTROPHINS GRANTSMANSHIPS GRAPHITISATION GRAPHITIZATION
HAEMATOPHAGOUS HAGIOGRAPHISTS HAIRSPLITTINGS HEPATICOLOGIES HEPATICOLOGIST
HEPATOMEGALIES HERPETOLOGICAL HETEROGRAPHIES HISTOPATHOLOGY HISTORIOGRAPHY
HYETOGRAPHICAL ICHTHYOPHAGIES ICHTHYOPHAGIST ICHTHYOPHAGOUS IMPARIDIGITATE
IMPIGNORATIONS IMPOSTHUMATING IMPREGNABILITY INCAPACITATING INTERCOMPARING
INTEROPERATING INTERPELLATING INTERPRETATING KINEMATOGRAPHS KINEMATOGRAPHY
LARYNGOSCOPIST LEGISLATORSHIP LETTERSPACINGS LEXICOGRAPHIST LIPOGRAMMATISM
LIPOGRAMMATIST LITHOGRAPHICAL LYMPHANGIOMATA LYMPHANGITIDES LYMPHANGITISES
MAGISTRATESHIP MAGNETOSPHERES MAGNETOSPHERIC MALIMPRINTINGS MASTIGOPHORANS
MASTIGOPHOROUS MEGALOPOLITANS METACOMPUTINGS METALLOGRAPHER METALLOGRAPHIC
METAMORPHOSING METAPSYCHOLOGY METEOROGRAPHIC MICROPEGMATITE MISPUNCTUATING
MOUSETRAPPINGS NEUROPATHOLOGY OBSTREPERATING ODONTOGRAPHIES OESOPHAGITISES
ONYCHOPHAGISTS OPHTHALMOLOGIC OPISTHOGLOSSAL OPISTHOGRAPHIC OPPIGNERATIONS
OPPIGNORATIONS ORGANOGRAPHIST ORTHOGRAPHICAL ORTHOGRAPHISTS OVERPOPULATING
PAGANISTICALLY PALAEBIOLOGIST PALAEETHNOLOGY PALAEOGRAPHIST PALAEOMAGNETIC
PALEOBIOLOGIST PALEOECOLOGIST PALEOMAGNETISM PALEOMAGNETIST PALEONTOLOGIES
PALEONTOLOGIST PALEOPATHOLOGY PALEOZOOLOGIST PALINGENESISTS PALINGENETICAL
PAMPHLETEERING PANGENETICALLY PANGRAMMATISTS PANTHEOLOGISTS PANTOGRAPHICAL
PANTOPRAGMATIC PARADIGMATICAL PARAGRAMMATIST PARALINGUISTIC PARAMAGNETISMS
PARAMETERISING PARAMETERIZING PARASITOLOGIES PARASITOLOGIST PARCHMENTISING
PARCHMENTIZING PARENTHESISING PARENTHESIZING PARLIAMENTINGS PARTRIDGEBERRY
PATHOBIOLOGIES PATHOLOGICALLY PEPTIDOGLYCANS PEREGRINATIONS PERINATOLOGIES
PERINATOLOGIST PETROGRAPHICAL PETROLOGICALLY PHANTASMAGORIA PHANTASMAGORIC
PHARMACOLOGIST PHARYNGOLOGIST PHARYNGOTOMIES PHLEGMATICALLY PHLEGMATICNESS
PHLOGISTICATED PHLOGISTICATES PHONAUTOGRAPHS PHONOGRAPHISTS PHOTOENGRAVERS
PHOTOENGRAVING PHOTOGENICALLY PHOTOGRAMMETRY PHOTOGRAPHICAL PHOTOGRAPHISTS
PHOTOTELEGRAMS PHOTOTELEGRAPH PHRASEOLOGISTS PHYTOGENETICAL PHYTOGEOGRAPHY
PHYTOLOGICALLY PHYTOPATHOGENS PHYTOPATHOLOGY PICTORIALISING PICTORIALIZING
PIDGINISATIONS PIDGINIZATIONS PIEZOMAGNETISM PLACENTOLOGIES PLAGIOTROPISMS
PLANETOLOGICAL PLANETOLOGISTS PLAYWRIGHTINGS PLECTOGNATHOUS PLETHYSMOGRAMS
PLETHYSMOGRAPH PNEUMATOLOGIES PNEUMATOLOGIST PNEUMOGASTRICS POLITICALISING
POLITICALIZING POSTCOLLEGIATE POSTGANGLIONIC POSTGRADUATION POSTSURGICALLY
PRAGMATICALITY PRAGMATISATION PRAGMATIZATION PREACQUAINTING PREARRANGEMENT
PREAUTHORIZING PRECONTRACTING PREDESIGNATING PREDESIGNATION PREDESIGNATORY
PREDESTINATING PREFABRICATING PREFIGURATIONS PREFORMULATING PREGNABILITIES
PRENEGOTIATING PRENEGOTIATION PREPONDERATING PRESANCTIFYING PRIMATOLOGICAL
PRIMATOLOGISTS PROBLEMATIZING PROGESTATIONAL PROGNOSTICATED PROGNOSTICATES
PROGNOSTICATOR PROPAGANDISTIC PROSTAGLANDINS PROTOLANGUAGES PSEUDOPREGNANT
PTERIDOLOGICAL PTERYLOGRAPHIC PUGILISTICALLY PYRAMIDOLOGIST PYROMETALLURGY
PYROPHOTOGRAPH RADIOAUTOGRAPH RADIOTELEGRAPH REAPPORTIONING RECAPITALISING
RECAPITALIZING RECAPITULATING REFLECTOGRAPHS REFLECTOGRAPHY REGISTRARSHIPS
REPARTITIONING REPHOTOGRAPHED REPRISTINATING ROENTGENOGRAPH ROENTGENOPAQUE
RONTGENOGRAPHS RONTGENOGRAPHY SAUROPTERYGIAN SCINTIGRAPHIES SELENOGRAPHIST
SEPTUAGENARIAN SEPTUAGENARIES SEXTUPLICATING SHAPESHIFTINGS SHARPSHOOTINGS
SOPHISTICATING SPAGHETTIFYING SPECTROGRAPHIC SPECTROLOGICAL SPELAEOLOGISTS
SPERMATOGENIES SPERMATOGENOUS SPERMATOGONIAL SPERMATOGONIUM SPHAGNOLOGISTS
SPIRITUALISING SPIRITUALIZING SPONGIOBLASTIC STEEPLECHASING STEGANOGRAPHER
STEGANOGRAPHIC STEGOCEPHALIAN STEGOCEPHALOUS STENOGRAPHICAL STENOGRAPHISTS
STEPPARENTINGS STEREOGRAPHIES STEREOGRAPHING STIGMATOPHILIA STRATIGRAPHERS
STRATIGRAPHIES STRATIGRAPHIST STYLOGRAPHICAL SUPERANNUATING SUPERDELEGATES
SUPERELEVATING SUPEREROGATING SUPEREROGATION SUPEREROGATIVE SUPEREROGATORS
SUPEREROGATORY SUPERGRAVITIES SUPEROVULATING SUPPLICATINGLY SUPRASEGMENTAL
SURROGATESHIPS SYCOPHANTISING SYCOPHANTIZING SYMPTOMATISING SYMPTOMATIZING
SYMPTOMATOLOGY TACHYGRAPHICAL TACHYGRAPHISTS TECHNOGRAPHIES TELAUTOGRAPHIC
TELEPHOTOGRAPH TETRASPORANGIA THALASSOGRAPHY THAUMATOGRAPHY THERMOGRAPHERS
THERMOGRAPHIES TRAINSPOTTINGS TRANSPLANTINGS TRANSPORTINGLY TRANSSHIPPINGS
TROPOCOLLAGENS TROPOLOGICALLY UNAPPETISINGLY UNAPPETIZINGLY UNDERPAINTINGS
UNDERSTRAPPING UNSYMPATHISING UNSYMPATHIZING UPGRADEABILITY UPSTANDINGNESS
URANOGRAPHISTS WATERPROOFINGS XYLOTYPOGRAPHY ZOOPATHOLOGIES