There are 547 twelve-letter words containing A, C, G, I and S, https://www.bestwordlist.com/c/a/5/12letterwordswithacgis.htm ACAROLOGISTS ACCESSIONING ACROMEGALICS ACROMEGALIES AEROBICISING AGARICACEOUS AGNOSTICISMS AGORAPHOBICS AGRICULTURES AGRIPRODUCTS AGROSTOLOGIC ALCOHOLISING ALGOLAGNIACS ANASTIGMATIC ANGIOCARPOUS ANGIOSARCOMA ANGLOMANIACS ANTAGONISTIC ARCHEOLOGIES ARCHEOLOGIST ARCHIPELAGOS ARGILLACEOUS ASCERTAINING ASEPTICISING ASEPTICIZING ASSURGENCIES ASTACOLOGIES ASTACOLOGIST ASTRINGENCES ASTROLOGICAL AUSCULTATING AUTECOLOGIES BACKCROSSING BACKFILLINGS BACKFITTINGS BACKPACKINGS BACKSHISHING BACKSLAPPING BACKSLIDINGS BACKSPEERING BACKSPEIRING BACKSTABBING BACKSTALLING BACKSTAMPING BACKSTARTING BACKSTOPPING BACKSTRAIGHT BACKSTROKING BAREBACKINGS BELLYACHINGS BENIGNANCIES BESCATTERING BIOMAGNETICS BLACKLISTING BLACKWASHING BLOGJACKINGS BLUEJACKINGS BRACHYLOGIES BRAGGADOCIOS BRICKLAYINGS BRICKMAKINGS BROADCASTING BUSHWHACKING CABLECASTING CACOGRAPHIES CAENOGENESIS CAINOGENESES CAINOGENESIS CALENDERINGS CALIGINOSITY CALLIBOGUSES CALLIGRAMMES CANDLELIGHTS CAPARISONING CAPITALISING CARAMELISING CARAVANNINGS CARDIOGRAPHS CARDIOLOGIES CARDIOLOGIST CARDSHARPING CARPHOLOGIES CARPOLOGISTS CARRAGEENINS CARRIAGEWAYS CASHMOBBINGS CASTIGATIONS CATABOLISING CATALOGISING CATALOGUISED CATALOGUISES CATALOGUISTS CATALOGUIZES CATECHISINGS CATECHIZINGS CATEGORISING CENTIGRAMMES CENTIMORGANS CENTRALISING CENTRIFUGALS CEPHALALGIAS CEPHALALGICS CERARGYRITES CEROGRAPHIES CEROGRAPHIST CHANDLERINGS CHANNELISING CHAPTALISING CHASMOGAMIES CHASTENINGLY CHAUFFEUSING CHEESEPARING CHIKUNGUNYAS CHIMICHANGAS CINEMATISING CIRCULATINGS CLADOGENESIS CLASSICISING CLASSICIZING CLEISTOGAMIC CLIFFHANGERS CLISTOGAMIES CLOISONNAGES COAGULATIONS COASTEERINGS COCKSWAINING COGNOMINATES COLLEGIALISM COLLEGIANERS COLLIGATIONS COLOGARITHMS COLORCASTING COLORWASHING COMMEASURING COMPAGINATES COMPENSATING COMPLAININGS CONCUBINAGES CONDENSATING CONFIGURATES CONFISCATING CONGELATIONS CONJUGATINGS CONJUGATIONS CONSECRATING CONSIGNATION CONSIGNATORY CONSOCIATING CONSTIPATING CONSTRAINING CONSUMMATING CONTAGIONIST CONTAGIOUSLY CONVALESCING CONVERSATING COPROPHAGIES COPROPHAGIST COPYREADINGS CORDIALISING CORRUGATIONS COSMOGONICAL COSMOGRAPHIC COSMOLOGICAL CRAGGINESSES CRAMPONNINGS CRANIOLOGIES CRANIOLOGIST CROSSBANDING CROSSBARRING CRYOSURGICAL CRYPTOGAMIES CRYPTOGAMIST CRYSTALISING CRYSTALIZING CYANOGENESIS CYCLOPLEGIAS DAMASCEENING DAMASCENINGS DECIMALISING DECREASINGLY DEGENERACIES DELOCALISING DEMOGRAPHICS DESCRAMBLING DEVOCALISING DIAGNOSTICAL DISACCORDING DISADVANCING DISAFFECTING DISANCHORING DISAVAUNCING DISAVOUCHING DISBRANCHING DISCANDERING DISCANDYINGS DISCOGRAPHER DISCOGRAPHIC DISCOURAGERS DISCOURAGING DISCULPATING DISSOCIATING ECHOGRAPHIES EGOISTICALLY ELASTICATING ELASTICISING ELASTICIZING EMASCULATING ENCOMPASSING ENCOURAGINGS EPISCOPATING ESCAPOLOGIES ESCAPOLOGIST ESCHATOLOGIC EULOGISTICAL EVANGELICALS EVANGELICISM EVANGELISTIC EVISCERATING EXACTINGNESS EXCOGITATORS FACSIMILEING FANATICISING FIRESCAPINGS FLASHBACKING FORECASTINGS FORESLACKING FRICASSEEING GALACTOSEMIA GALACTOSEMIC GALACTOSIDES GALLINACEANS GALLINACEOUS GALLSICKNESS GALRAVITCHES GANCICLOVIRS GASIFICATION GASOMETRICAL GASTROCNEMII GASTRONOMICS GASTROSCOPIC GASTROTRICHS GATECRASHING GEANTICLINES GEMEINSCHAFT GENERATRICES GENOCIDAIRES GEOGNOSTICAL GEOLOCATIONS GEOMECHANICS GEOSTRATEGIC GEOSYNCLINAL GERANIACEOUS GESTICULATED GESTICULATES GESTICULATOR GIGANTICIDES GIGANTICNESS GILRAVITCHES GLACIOLOGIES GLACIOLOGIST GLOSSEMATICS GLUCOKINASES GLUCOSAMINES GLUCOSIDASES GLYCERINATES GLYCOSIDASES GOALKICKINGS GRACIOSITIES GRACIOUSNESS GRADUALISTIC GRAMINACEOUS GRAMMATICISE GRAMMATICISM GRANOLITHICS GRAPHICACIES GRASSCYCLING GRASSFINCHES GRECIANISING GREENBACKISM GRIDDLECAKES GYMNASIARCHS GYNECOMASTIA HAGIOCRACIES HAIRCUTTINGS HAMSHACKLING HELICOGRAPHS HIGHJACKINGS HISTOLOGICAL HORSERACINGS HYGROCHASIES HYGROCHASTIC HYPERALGESIC HYPSOGRAPHIC IMMIGRANCIES INCANDESCING INCOGNISABLE INCOGNISANCE INCRASSATING INCREASINGLY INELEGANCIES INFOGRAPHICS INGRAVESCENT INOSCULATING INTERCHANGES INTERFACINGS INTERSPACING ISOANTIGENIC ISOMAGNETICS KICKSTARTING KNEECAPPINGS LANDSCAPINGS LATCHSTRINGS LEGITIMACIES LEXICALISING LIMACOLOGIES LIMACOLOGIST LINEBACKINGS LINECASTINGS LINGUISTICAL LOGANIACEOUS LOGICALITIES LOGISTICALLY LOGISTICIANS LOGOMACHISTS MACADAMISING MAGISTRACIES MAGNETICIANS MALACOLOGIES MALACOLOGIST MALIGNANCIES MARCONIGRAMS MATCHMAKINGS MEATPACKINGS MEDICALISING MERCHANTINGS METATUNGSTIC MICROGAMETES MICROMANAGES MICROPHAGOUS MINICABBINGS MISBALANCING MISCARRIAGES MISCATALOGED MISCATALOGUE MISCEGENATED MISCEGENATES MISCEGENATOR MISCHALLENGE MISEDUCATING MISGUIDANCES MISPACKAGING MONARCHISING MONOGAMISTIC MUCILAGINOUS MUSEOLOGICAL MUSICALISING MUSICALIZING MYCOPHAGISTS MYSTAGOGICAL NEGATIVISTIC NEWSAGENCIES NEWSCASTINGS NIGHTCLASSES NIGROMANCIES NOCTIVAGANTS NONSTRATEGIC NOSTOLOGICAL NUCLEARISING OCEANOLOGIES OCEANOLOGIST OCTOGENARIES OLIGOCHAETES OPPUGNANCIES ORGANICISTIC ORGANICITIES ORGASMICALLY ORGASTICALLY OSCILLOGRAMS OSCILLOGRAPH OSTEOLOGICAL OUTSCREAMING OVERCASTINGS OVERCOATINGS PACESETTINGS PACKINGHOUSE PANICMONGERS PARACHUTINGS PARALOGISTIC PARASCENDING PARATUNGSTIC PASSACAGLIAS PEACEMAKINGS PESTOLOGICAL PHAGOCYTISED PHAGOCYTISES PHAGOCYTISMS PHAGOCYTIZES PHAGOCYTOSIS PHAGOMANIACS PHRASEOLOGIC PLAGIARISTIC PLAGIOCLASES PLASTICISING PLASTICIZING POSTORGASMIC POSTSURGICAL PRAGMATICISM PRAGMATICIST PRAGMATISTIC PRECOGNISANT PREDECEASING PREDISCHARGE PROFLIGACIES PUGILISTICAL PUGNACIOUSLY QUACKSALVING QUINDECAGONS RACEWALKINGS RADICALISING RANSHACKLING RECANALISING RECOGNISABLE RECOGNISABLY RECOGNISANCE REESCALATING REFINANCINGS REGENERACIES REINCREASING REPUGNANCIES REPURCHASING ROPEDANCINGS ROUGHCASTING RUSTICATINGS SACCHARISING SACCHARIZING SACRAMENTING SACRILEGIOUS SACRILEGISTS SAFECRACKING SALICYLATING SANCTIFYINGS SANCTIONINGS SATISFICINGS SCAFFOLDINGS SCAMBAITINGS SCANDALISING SCANDALIZING SCAPEGOATING SCAPEGOATISM SCARIFYINGLY SCATOLOGICAL SCATOLOGISTS SCATOPHAGIES SCATTERINGLY SCATTERLINGS SCAVENGERIES SCAVENGERING SCENOGRAPHIC SCHEMATISING SCHEMATIZING SCINTIGRAPHY SCRAMBLINGLY SCRAPBOOKING SCRATCHINGLY SCRIMSHAWING SEARCHLIGHTS SECRETAGOGIC SECULARISING SECULARIZING SEMIOLOGICAL SHELLACKINGS SIDETRACKING SIGNIFICANCE SIGNIFICANCY SIGNIFICANTS SIGNIFICATES SIGNIFICATOR SIMULCASTING SINGLETRACKS SLACKLININGS SOCIALISINGS SOCIALIZINGS SOCIOLOGICAL SPACEFARINGS SPACEFLIGHTS SPACEWALKING SPAGYRICALLY SPECIALISING SPECIALIZING SPECIALOGUES SPEECHMAKING SPHACELATING SPHRAGISTICS SPIFLICATING SPIROGRAPHIC STAIRCASINGS STANCHELLING STANCHIONING STARFUCKINGS STENOGRAPHIC STEPDANCINGS STERCORATING STOCKTAKINGS STYLOGRAPHIC SUBGLACIALLY SUBMICROGRAM SUBSTRACTING SUFFOCATINGS SUGARCOATING SUPERGLACIAL SUPERORGANIC SUPPLICATING SURFCASTINGS SYMBOLOGICAL SYNERGICALLY TERMAGANCIES TOWNSCAPINGS TRACKLAYINGS TRAFFICKINGS TRAGICALNESS TRANSCENDING TRANSCRIBING TRANSFECTING TSUNAMIGENIC TYPECASTINGS UNCANONISING UNCARINGNESS UNCOALESCING UNDISCHARGED UNGRACIOUSLY UNGUICULATES UNSCRAMBLING VAGINICOLOUS VESICULATING VICTUALLAGES VOUCHSAFINGS WAINSCOTINGS WAINSCOTTING WAISTCOATING WALKINGSTICK WARCHALKINGS WATCHMAKINGS WATCHSPRINGS WILDCATTINGS WISECRACKING WITCHGRASSES WOODCARVINGS