There are 521 twelve-letter words containing A, D, H and I, https://www.bestwordlist.com/c/a/4/12letterwordswithadhi.htm
ABSINTHIATED ACCOMPLISHED ACHLORHYDRIA ACHLORHYDRIC ACHROMATISED
ACHROMATIZED ACIDANTHERAS ACIDOPHILOUS ADENOPATHIES ADHESIVENESS
ADIAPHORISMS ADIAPHORISTS ADMIRALSHIPS ADMONISHMENT ADVISERSHIPS
AFFRANCHISED AFFRIGHTEDLY AFFRIGHTENED AGATHODAIMON AIRFREIGHTED
ALDERMANSHIP ALPHABETISED ALPHABETIZED AMIANTHOIDAL AMPHIDENTATE
AMPHIDIPLOID ANAPHRODISIA ANESTHETISED ANESTHETIZED ANTHEROZOIDS
ANTHEROZOOID ANTHOLOGISED ANTHOLOGIZED ANTHROPOIDAL ANTICATHODES
ANTIHYDROGEN APHRODISIACS APOTHEOSISED APOTHEOSIZED APPREHENDING
ARCHDIOCESAN ARCHDIOCESES ASPHETERISED ASPHETERIZED AUDITORSHIPS
BACKSTITCHED BALLHANDLING BIGHEARTEDLY BIOGRAPHISED BIOGRAPHIZED
BIOHAZARDOUS BIRDWATCHERS BIRDWATCHING BLANDISHMENT BODDHISATTVA
BODHISATTVAS BONDMANSHIPS BRANCHIOPODS BRIDEWEALTHS CALLIGRAPHED
CANDLEFISHES CANDLELIGHTS CANTHARIDIAN CANTHARIDINS CARDINALSHIP
CARDIOGRAPHS CARDIOGRAPHY CARDSHARPING CATHETERISED CATHETERIZED
CATHIODERMIE CATHODICALLY CATHOLICISED CATHOLICIZED CEPHALOPODIC
CHALCEDONIES CHALCOGENIDE CHAMBERMAIDS CHANDELIERED CHANDLERINGS
CHARIOTEERED CHEERLEADING CHILDBEARING CHILDERMASES CHILIAHEDRON
CHIMNEYBOARD CHLORIDATING CHONDROSTIAN COACHBUILDER COMRADESHIPS
CONCHOIDALLY CYANOHYDRINS DAMSELFISHES DAUGHTERLIER DAUGHTERLING
DAUPHINESSES DAYLIGHTINGS DEBAUCHERIES DECHLORINATE DECIPHERABLE
DEGARNISHING DEHORTATIONS DEHUMANISING DEHUMANIZING DEHYDRATIONS
DEMOGRAPHICS DEMOGRAPHIES DEMOGRAPHIST DIACHRONISMS DIAMORPHINES
DIAPHANOUSLY DIAPHORETICS DIAPHRAGMING DIAPOPHYSIAL DIARTHRODIAL
DIASTROPHISM DIATHERMANCY DIAZOMETHANE DIBRANCHIATE DICEPHALISMS
DICHOTICALLY DICHROMATICS DICHROMATISM DICTATORSHIP DIENCEPHALIC
DIENCEPHALON DIETHYLAMIDE DIETHYLAMINE DILETTANTISH DIMINISHABLE
DIPHOSPHATES DISACCHARIDE DISACCHARIDS DISANCHORING DISAUTHORISE
DISAUTHORIZE DISAVOUCHING DISBRANCHING DISCOGRAPHER DISCOGRAPHIC
DISCOPHORANS DISENCHAINED DISENCHANTED DISENCHANTER DISENTHRALLS
DISESTABLISH DISFRANCHISE DISGARNISHED DISGARNISHES DISHALLOWING
DISHARMONIES DISHARMONISE DISHARMONIZE DISHEARTENED DISHONORABLE
DISHONORABLY DISHWASHINGS DISSHEATHING DISTRAUGHTLY DITHEISTICAL
DITHELETICAL DITHYRAMBIST DITTOGRAPHIC DODECAPHONIC DOLLARFISHES
DOLPHINARIUM DOOMWATCHING DOXOGRAPHIES DRAGONFISHES DRAUGHTINESS
DROMOPHOBIAS DWARFISHNESS DYSAESTHESIA DYSAESTHETIC DYSRHYTHMIAS
ECHINODERMAL EDAPHOLOGIES ENARTHRODIAL ENDOTHELIOMA ENFRANCHISED
EPHEMERIDIAN ETHEREALISED ETHEREALIZED ETHIONAMIDES ETHNOMEDICAL
EUTHANATISED EUTHANATIZED EXHEREDATING EXHEREDATION FAINTHEARTED
FARSIGHTEDLY FARTHINGLAND FELDSPATHOID FELSPATHOIDS FIANCHETTOED
FOOLHARDIEST FOOLHARDISES FOOLHARDIZES FOUNTAINHEAD GALRAVITCHED
GILRAVITCHED GODFATHERING GRADUATESHIP GRANDEESHIPS GUANETHIDINE
GUARDIANSHIP HAEMODYNAMIC HAEMORRHOIDS HAEMOSIDERIN HAIRBREADTHS
HAIRDRESSERS HAIRDRESSING HAIRSBREADTH HALFWITTEDLY HALLUCINATED
HALOPERIDOLS HANDBAGGINGS HANDCRAFTING HANDFASTINGS HANDICAPPERS
HANDICAPPING HANDICRAFTER HANDKERCHIEF HANDSHAKINGS HANDSTAMPING
HANDWRINGERS HANDWRITINGS HANSARDISING HANSARDIZING HARBOURSIDES
HARDINGGRASS HARDSTANDING HARLEQUINADE HARMONICHORD HARPSICHORDS
HARUSPICATED HEADBANGINGS HEADHUNTINGS HEADMISTRESS HEADREACHING
HEADSHRINKER HEARTRENDING HELICOIDALLY HELIOGRAPHED HEMICHORDATE
HEMIHYDRATED HEMIHYDRATES HEMODIALYSES HEMODIALYSIS HEMODIALYZER
HEMODYNAMICS HEMORRHOIDAL HERALDICALLY HERBICIDALLY HEREDITAMENT
HEREDITARIAN HEREDITARILY HEXACHLORIDE HEXADACTYLIC HEXADECANOIC
HEXADECIMALS HEXAFLUORIDE HEXAGRAMMOID HEXAMETRISED HEXAMETRIZED
HEXAPLOIDIES HIERARCHISED HIERARCHIZED HINDQUARTERS HIPPODAMISTS
HISPANICISED HISPANICIZED HOLIDAYMAKER HOLLANDAISES HOMESTEADING
HORRIPILATED HOSPITALISED HOSPITALIZED HUSBANDLIEST HYBRIDISABLE
HYBRIDIZABLE HYDATIDIFORM HYDRALAZINES HYDRARGYRIAS HYDRARGYRISM
HYDRASTININE HYDRAULICKED HYDROCEPHALI HYDRODYNAMIC HYDROELASTIC
HYDROGRAPHIC HYDROLOGICAL HYDROMANCIES HYDRONICALLY HYDROPATHICS
HYDROPATHIES HYDROPATHIST HYDROPHOBIAS HYDROPLANING HYDROSTATICS
HYPERACIDITY HYPERDULICAL HYPNOPAEDIAS HYPOCHONDRIA HYPOSTASISED
HYPOSTASIZED HYPOSTATISED HYPOSTATIZED HYRACOIDEANS ICOSAHEDRONS
IDEOGRAPHIES IMMETHODICAL INDOMETHACIN INTERCHAINED INTERCHANGED
INTERDASHING INVALIDHOODS ISODIAPHERES JADISHNESSES KALEIDOPHONE
KITCHENMAIDS LANDHOLDINGS LEUCITOHEDRA LIGHTHEARTED LITHOGRAPHED
LYMPHOMATOID MACHAIRODONT MACHICOLATED MALNOURISHED MARISCHALLED
MATHEMATISED MATHEMATIZED MEDIATORSHIP MERCHANDISED MERCHANDISER
MERCHANDISES MERCHANDIZED MERCHANDIZER MERCHANDIZES METATHESISED
METATHESIZED METHANAMIDES METHODICALLY MICROGRAPHED MIDSHIPMATES
MIMEOGRAPHED MISAPPREHEND MISCHANNELED MISHANDLINGS MITHRIDATISE
MITHRIDATISM MITHRIDATIZE MITOCHONDRIA MONODELPHIAN MOUSTACHIOED
MULTIWARHEAD NAPHTHALISED NAPHTHALIZED NIKETHAMIDES OCTAHEDRITES
ODONTOPHOBIA OPHIDIARIUMS ORCHIDACEOUS ORCHIDOMANIA ORTHODONTIAS
ORTHOPAEDICS ORTHOPAEDIES ORTHOPAEDIST ORTHOPEDICAL ORTHOVANADIC
OUTLANDISHLY OVERACHIEVED OVERHANDLING OVERLAVISHED PACHYDERMIAS
PADDLEFISHES PAEDOMORPHIC PAEDOPHILIAC PAEDOPHILIAS PAEDOPHILICS
PARASPHENOID PARATHYROIDS PARATYPHOIDS PATHFINDINGS PATHOLOGISED
PATHOLOGIZED PEDOPHILIACS PERICHONDRAL PERICHONDRIA PHAGOCYTISED
PHAGOCYTIZED PHILADELPHUS PHILANDERERS PHILANDERING PHOSPHATIDES
PHOSPHATIDIC PHOSPHATIDYL PHOSPHATISED PHOSPHATIZED PHOTODYNAMIC
PHYSICALIZED PHYTONADIONE PREDISCHARGE PREHARDENING PSYCHEDELIAS
PSYCHODELIAS PUMPHANDLING PYRITOHEDRAL QUADRAPHONIC QUADRIPHONIC
QUADROPHONIC RADIESTHESIA RADIESTHETIC RADIOCHEMIST RADIOGRAPHED
RADIOGRAPHER RADIOGRAPHIC RADIOPHONICS RADIOPHONIES RADIOPHONIST
RADIOTHERAPY RADIOTHORIUM REAUTHORISED REAUTHORIZED REEMPHASISED
REEMPHASIZED REHARMONIZED REHYDRATIONS RHAPSODISING RHAPSODISTIC
RHAPSODIZING RIDESHARINGS ROADHOLDINGS ROADWORTHIER ROADWORTHIES
SACCHARIFIED SACCHAROIDAL SANDCHERRIES SCHISMATISED SCHISMATIZED
SCRATCHBUILD SCRIMSHANDER SCRIMSHANKED SEMIDETACHED SHADOWBOXING
SHAREHOLDING SHERARDISING SHERARDIZING SHIRTWAISTED SINDONOPHANY
SKRIMSHANKED SLAVEHOLDING SMALLHOLDING SPEARHEADING SPHEROIDALLY
STAKEHOLDING STAPHYLINIDS STAYSTITCHED STEWARDSHIPS STICKHANDLED
STICKHANDLER STICKHANDLES STRAIGHTBRED STRAIGHTEDGE STRAIGHTENED
STRINGHALTED SUBARACHNOID SULPHADOXINE SULPHONAMIDE SWITCHBACKED
SWITCHBLADES SWITCHBOARDS SYNADELPHITE TACHYCARDIAC TACHYCARDIAS
TELEPATHISED TELEPATHIZED TENDINOPATHY TETRAHEDRITE THALIDOMIDES
THEATRICISED THEATRICIZED THIORIDAZINE THIRDSTREAMS THITHERWARDS
TRACHEITIDES TRAITORHOODS TRANSSHIPPED TRIADELPHOUS TRICHOMONADS
TROCHOIDALLY UNADMONISHED UNAUTHORISED UNAUTHORIZED UNDERACHIEVE
UNDERHANDING UNDERHEATING UNDISCHARGED UNDISPATCHED UNEMPHASISED
UNEMPHASIZED UNFRANCHISED UNHABITUATED UNINHABITEDS UNMECHANISED
UNMECHANIZED UNMETHODICAL UNVANQUISHED VAIVODESHIPS VIDEOGRAPHER
WATCHDOGGING WHILLYWHAWED WHISKERANDOS WHITHERWARDS WINDCHEATERS
WITHDRAWABLE WITHDRAWMENT WITHSTANDERS WITHSTANDING XANTHOCHROID
ZANTEDESCHIA