There are 405 fifteen-letter words containing 2A, P, S and T, https://www.bestwordlist.com/c/a/5/15letterwordswithaapst.htm ACCEPTABILITIES ACCOUNTANTSHIPS ACHONDROPLASTIC ACROPARESTHESIA ACTINOTHERAPIES ADAPTABLENESSES ALLOTETRAPLOIDS ALPHABETISATION AMINOPEPTIDASES ANISOTROPICALLY ANTAPHRODISIACS ANTHROPOLATRIES ANTHROPOPATHIES ANTHROPOPATHISM ANTHROPOPHAGIES ANTHROPOPHAGOUS ANTHROPOPHOBIAS ANTIAPHRODISIAC ANTICAPITALISMS ANTICAPITALISTS ANTIDEPRESSANTS ANTINEOPLASTICS ANTIPERISTALSES ANTIPERISTALSIS ANTIPERISTALTIC ANTIPERSPIRANTS ANTIREPUBLICANS ANTISEPARATISTS ANTISPECULATION ANTISPECULATIVE ANTITRANSPIRANT APOCALYPTICISMS APOLITICALITIES APOPHTHEGMATISE APOPHTHEGMATIST APOTHEGMATISING APPEALABILITIES APPLICABILITIES APPROPRIATENESS ARCHAEOPTERYXES ARCHIEPISCOPATE AROMATHERAPISTS ARTERIOGRAPHIES ASTROPHOTOGRAPH ASTROPHYSICALLY ATMOSPHERICALLY AUTOBIOGRAPHERS AUTOBIOGRAPHIES AUTORADIOGRAPHS AUTOTETRAPLOIDS BACTERIOPHAGIES BACTERIOPHAGOUS BALNEOTHERAPIES BATRACHOPHOBIAS BIOSTRATIGRAPHY BIPARTISANSHIPS BIPOLARISATIONS BIPOLARIZATIONS BLAXPLOITATIONS BRACHYTHERAPIES CAPITALISATIONS CAPITALIZATIONS CARPETBAGGERIES CARPOMETACARPUS CASTANOSPERMINE CATHODOGRAPHERS CATHODOGRAPHIES CEPHALOTHORACES CEPHALOTHORAXES CHALCOGRAPHISTS CHANNELOPATHIES CHAPTALISATIONS CHAPTALIZATIONS CLAUSTROPHILIAS CLAUSTROPHOBIAS CLIMATOGRAPHIES COMMANDANTSHIPS COMPARABILITIES COMPARATIVENESS COMPASSIONATELY COMPASSIONATING CONTEMPORANEANS CONTRAPUNTALIST CRYPTAESTHESIAS CRYSTALLOGRAPHY CYTOPLASMICALLY DACTYLOGRAPHERS DACTYLOGRAPHIES DEPARTMENTALISE DEPARTMENTALISM DEPOLARISATIONS DEPOLARIZATIONS DERMATOGRAPHIAS DERMATOGRAPHIES DERMATOPLASTIES DEXAMPHETAMINES DIAPHRAGMATITIS DIAPHRAGMITISES DIASTROPHICALLY DISAPPLICATIONS DISAPPROBATIONS DISAPPROPRIATED DISAPPROPRIATES DISCAPACITATING DISPARATENESSES DISPASSIONATELY DRAUGHTSMANSHIP ECOCATASTROPHES EMANCIPATIONIST ENDOPARASITISMS EPIGRAMMATISERS EPIGRAMMATISING EPIGRAMMATIZERS ESEMPLASTICALLY EVAPORABILITIES EXPANDABILITIES GALACTOPOIETICS GALVANOPLASTIES GALVANOTROPISMS GRAPHITISATIONS GRAPHITIZATIONS HEADMASTERSHIPS HEPARINISATIONS HEPARINIZATIONS HOMOPLASTICALLY HOMOTRANSPLANTS HOSPITALISATION HOSPITALIZATION HYDROXYAPATITES HYPERAESTHESIAS HYPERCATABOLISM HYPERNATRAEMIAS HYPERPARASITISM HYPERSALIVATION HYPOSTASISATION HYPOSTASIZATION HYPOSTATISATION HYPOSTATIZATION IMPALPABILITIES IMPARTIALNESSES IMPASSABILITIES IMPLACABILITIES IMPRACTICALNESS IMPROVISATIONAL IMPROVISATORIAL INAPPRECIATIONS INCAPACITATIONS INSPIRATIONALLY INTERPAROXYSMAL JUXTAPOSITIONAL LAPIDIFICATIONS LIPOGRAMMATISMS LIPOGRAMMATISTS LYMPHOSARCOMATA MAGISTRATESHIPS MALAPPROPRIATES MALPRESENTATION MASSOTHERAPISTS MESATICEPHALIES MESATICEPHALOUS METALLOGRAPHERS METALLOGRAPHIES METALLOGRAPHIST MISACCEPTATIONS MISAPPLICATIONS MISAPPRECIATING MISAPPRECIATION MISAPPRECIATIVE MISAPPROPRIATED MISAPPROPRIATES MULTIPARAMETERS NEPHROBLASTOMAS NONENCAPSULATED NONPARTICIPANTS NONPARTISANSHIP NONPARTIZANSHIP NONSPECTACULARS NUCLEOPLASMATIC OPERATIONALISMS OPERATIONALISTS OPTIMALISATIONS OPTIMALIZATIONS ORGANOGRAPHISTS ORGANOPHOSPHATE ORGANOTHERAPIES OSTEOPATHICALLY OVERCAPITALISED OVERCAPITALISES OVERCAPITALIZES PAINSTAKINGNESS PALAEBIOLOGISTS PALAEOBIOLOGIST PALAEOBOTANISTS PALAEOECOLOGIST PALAEOGRAPHISTS PALAEOMAGNETISM PALAEOMAGNETIST PALAEONTOLOGIES PALAEONTOLOGIST PALAEOZOOLOGIST PALATABLENESSES PALATALISATIONS PALATALIZATIONS PALEOMAGNETISMS PALEOMAGNETISTS PANOPHTHALMITIS PANTHEISTICALLY PANTISOCRATICAL PANTISOCRATISTS PANTOPRAGMATICS PARABOLISATIONS PARABOLIZATIONS PARAGRAMMATISTS PARALINGUISTICS PARAMETRISATION PARANORMALITIES PARASEXUALITIES PARASITICALNESS PARASITISATIONS PARASITIZATIONS PARASITOLOGICAL PARASITOLOGISTS PARASYMPATHETIC PARLIAMENTARISM PARTHENOCARPIES PARTHENOCARPOUS PARTICIPATORIES PARTICULARISERS PARTICULARISING PARTICULARISTIC PARTICULARITIES PARTICULARIZERS PARTURIFACIENTS PASTEURISATIONS PASTEURIZATIONS PATENTABILITIES PATERFAMILIASES PATRIALISATIONS PATRIALIZATIONS PATRIARCHALISMS PATRIFOCALITIES PENTADACTYLISMS PERGAMENTACEOUS PERISTALTICALLY PERSONALISATION PERSONALIZATION PHANTASMAGORIAL PHANTASMAGORIAS PHANTASMAGORIES PHANTASMALITIES PHARMACEUTICALS PHARMACOGNOSIST PHARMACOGNOSTIC PHARMACOLOGISTS PHARMACOPOEISTS PHARMACOPOLISTS PHOSPHATISATION PHOSPHATIZATION PHTHALOCYANINES PLAGIOSTOMATOUS PLAINCLOTHESMAN PLANTAGINACEOUS PLASMOLYTICALLY PLASTICISATIONS PLASTICIZATIONS PLATINOCYANIDES PLURALISTICALLY POLYUNSATURATED POLYUNSATURATES POPULARISATIONS POPULARIZATIONS POSTAPOCALYPSES POSTAPOCALYPTIC POSTCONSONANTAL POSTDEVALUATION POSTGRADUATIONS POSTIRRADIATION POSTMILLENARIAN POSTULATIONALLY POSTVACCINATION PRACTICABLENESS PRACTICALNESSES PRAGMATICALNESS PRAGMATISATIONS PRAGMATIZATIONS PREANAESTHETICS PREARRANGEMENTS PREDESTINARIANS PREFABRICATIONS PREINSTALLATION PREMANUFACTURES PRESYNAPTICALLY PROCRASTINATING PROCRASTINATION PROCRASTINATIVE PROCRASTINATORS PROCRASTINATORY PROLETARIANISED PROLETARIANISES PROLETARIANISMS PROLETARIANIZES PROLETARIANNESS PROPAGABILITIES PROTHONOTARIATS PROTOSPATHAIRES PROTOSPATHARIUS PRUSSIANISATION PRUSSIANIZATION PSEUDAESTHESIAS PSYCHIATRICALLY PURITANICALNESS RADICULOPATHIES RADIOAUTOGRAPHS RADIOTELEGRAPHS RADIOTHERAPISTS REAPPRAISEMENTS RECAPITULATIONS REIMPLANTATIONS REPAIRABILITIES REPEATABILITIES REPOLARISATIONS REPOLARIZATIONS REPRIVATISATION SAPONIFICATIONS SAPROPHYTICALLY SAUROPTERYGIANS SEMIPARASITISMS SEMITRANSPARENT SEPTUAGENARIANS SLUMPFLATIONARY SPATIALISATIONS SPATIALIZATIONS SPECIALISATIONS SPECIALIZATIONS SPERMATOBLASTIC SPERMATORRHOEAS SPHAEROCRYSTALS SPIROCHAETAEMIA SPREADABILITIES STAPHYLOPLASTIC STAPHYLORRHAPHY STEGANOGRAPHERS STEGANOGRAPHIES STEGANOGRAPHIST STEGOCEPHALIANS STEREOGRAPHICAL STIGMATOPHILIAS STOMATOPLASTIES STRATIGRAPHICAL STRATIGRAPHISTS STRATOSPHERICAL SUBPROLETARIATS SULPHACETAMIDES SULPHATHIAZOLES SUPERABUNDANTLY SUPERADDITIONAL SUPERANNUATIONS SUPERBUREAUCRAT SUPEREXALTATION SUPERNATIONALLY SUPERNATURALISE SUPERNATURALISM SUPERNATURALIST SUPERNATURALIZE SUPERPARASITISM SUPERSATURATING SUPERSATURATION SUPRANATIONALLY SYCOPHANTICALLY SYMPATHETICALLY SYMPTOMATICALLY SYNAPOSEMATISMS TELAUTOGRAPHIES TETRASPORANGIUM THALASSOGRAPHER THALASSOGRAPHIC THALASSOTHERAPY THANATOGRAPHIES THORACOPLASTIES TRANSCRIPTIONAL TRANSPARENTISED TRANSPARENTISES TRANSPARENTIZED TRANSPARENTIZES TRANSPARENTNESS TRANSPIRATIONAL TRANSPLANTATION TRANSPORTATIONS TRANSPOSABILITY TRANSPOSITIONAL TROPICALISATION TRYPANOSOMIASES TRYPANOSOMIASIS ULTRACREPIDATES ULTRASONOGRAPHY UNAPOSTOLICALLY UNAPPRECIATIONS UNCOMPASSIONATE UNCOMPLAISANTLY UNDERCAPITALISE UNPRACTICALNESS UNSPECTACULARLY UPGRADABILITIES VAPOURABILITIES XENOTRANSPLANTS