There are 513 twelve-letter words containing A, D, E, P and R, https://www.bestwordlist.com/c/a/5/12letterwordswithadepr.htm
ADRENOCEPTOR ADVISERSHIPS AECIDIOSPORE AECIDOSPORES ALDERMANSHIP
ANTEPRANDIAL ANTIPERIODIC ANTIPREDATOR APERIODICITY APFELSTRUDEL
APODYTERIUMS APPENDICULAR APPREHENDING APPROPINQUED APPROPRIATED
APPROXIMATED ASPHETERISED ASPHETERIZED BASIDIOSPORE BIOGRAPHISED
BIOGRAPHIZED BOILERPLATED BOOTSTRAPPED BRADYPEPTICS CALLIGRAPHED
CAMELEOPARDS CAMPODEIFORM CANDLEPOWERS CARDIOPLEGIA CARDSHARPERS
CARPETBAGGED CARROTTOPPED CHOREGRAPHED CLAPPERBOARD COMRADESHIPS
CONSTUPRATED COPYREADINGS CORPORATISED CORPORATIZED COUNTERPLEAD
DAPPERNESSES DEASPIRATING DEASPIRATION DECAPITATORS DECIPHERABLE
DECREPITATED DECREPITATES DEEPWATERMAN DEEPWATERMEN DEMOGRAPHERS
DEMOGRAPHICS DEMOGRAPHIES DEMOGRAPHIST DEPARTEMENTS DEPARTMENTAL
DEPAUPERATED DEPAUPERATES DEPAUPERISED DEPAUPERISES DEPAUPERIZED
DEPAUPERIZES DEPHLEGMATOR DEPILATORIES DEPLORATIONS DEPOLARISERS
DEPOLARISING DEPOLARIZERS DEPOLARIZING DEPOPULATORS DEPORTATIONS
DEPOSITARIES DEPRAVATIONS DEPRAVEDNESS DEPRAVEMENTS DEPRECATIONS
DEPRECIATING DEPRECIATION DEPRECIATIVE DEPRECIATORS DEPRECIATORY
DEPREDATIONS DEPRIVATIONS DEPROGRAMING DEPROGRAMMED DEPROGRAMMER
DEPROGRAMMES DERMAPLANING DERMAPTERANS DERMATOPHYTE DESIPRAMINES
DESPAIRINGLY DESPERATIONS DESPOTOCRACY DESULPHURATE DEUTERANOPES
DEUTERANOPIA DEUTERANOPIC DEUTEROPLASM DIAGEOTROPIC DIAMORPHINES
DIAPHORETICS DICARPELLARY DICTYOPTERAN DIMERCAPROLS DIPROPELLANT
DIPTEROCARPS DISAPPEARING DISAPPROVERS DISCEPTATORS DISCOGRAPHER
DISCORPORATE DISCREPANCES DISCREPANTLY DISOPERATION DISPAUPERING
DISPAUPERISE DISPAUPERIZE DISPENSARIES DISPENSATORS DISPENSATORY
DISPLEASURED DISPLEASURES DISPRIVACIED DISPROPRIATE DISREPUTABLE
DISREPUTABLY DISTEMPERATE DOCKWALLOPER DOPAMINERGIC DOPPELGANGER
DOXOGRAPHERS DOXOGRAPHIES DRAFTSPEOPLE DRAFTSPERSON DRAPEABILITY
DUPLICATURES DYSPAREUNIAS EAVESDROPPED EAVESDROPPER EMPARADISING
ENDOPARASITE EPHEMERIDIAN EXPECTORATED EXPROPRIATED EXTRAPOLATED
FLAMEPROOFED FLAPPERHOODS FRANKPLEDGES GLASSPAPERED GRADUATESHIP
GRANDEESHIPS GRANDNEPHEWS GRANDPAPPIES GRANDPARENTS HALOPERIDOLS
HAMPEREDNESS HANDICAPPERS HANDYPERSONS HARUSPICATED HECTOGRAPHED
HELIOGRAPHED HEPTAHEDRONS HORRIPILATED HYDNOCARPATE HYDROCEPHALI
HYDROCEPHALY HYDROGRAPHER HYDROPATHIES HYDROTHERAPY HYPERACIDITY
HYPERCHARGED HYPERDACTYLY HYPERDULICAL IDEOGRAPHIES IDEOPRAXISTS
IMPENETRATED IMPERFORATED IMPERIALISED IMPERIALIZED IMPERSONATED
IMPIGNORATED IMPONDERABLE IMPONDERABLY IMPROPRIATED IMPROVISATED
INCORPORATED INTERPLANTED INTERPLEADED INTERPLEADER INTERPOLATED
ISODIAPHERES JELLYGRAPHED JEOPARDISING JEOPARDIZING JEOPARDOUSLY
LAMPADEDROMY LEOPARDESSES LEOPARDSKINS LEPIDOPTERAN LITHOGRAPHED
LOUDSPEAKERS MADREPORIANS MADREPORITES MADREPORITIC MALIMPRINTED
MANSPREADERS MANSPREADING MEDIATORSHIP METAPERIODIC MICROGRAPHED
MIMEOGRAPHED MISAPPREHEND MISPERSUADED MISPERSUADES MISPROGRAMED
MOUSETRAPPED MUCKSPREADER NEWSPAPERDOM OBTEMPERATED OPPIGNERATED
OPPIGNORATED ORTHOPAEDICS ORTHOPAEDIES ORTHOPAEDIST ORTHOPEDICAL
OUTSPREADING OVERCANOPIED OVEREXPANDED OVEROPERATED OVERPACKAGED
OVERPEDALING OVERPEDALLED OVERPERSUADE OVERPREPARED PACHYDERMIAS
PACHYDERMOUS PADDLEBOARDS PAEDERASTIES PAEDIATRISTS PAEDOMORPHIC
PAMPEREDNESS PAPPARDELLES PARADOXURINE PARAHYDROGEN PARALDEHYDES
PARALLELISED PARALLELIZED PARAMEDICALS PARAMETRISED PARAMETRIZED
PARAPERIODIC PARAQUADRATE PARASCENDERS PARASCENDING PARASITICIDE
PARASPHENOID PARASUICIDES PARFOCALISED PARFOCALIZED PARTICIPATED
PARTICOLORED PASQUINADERS PASTURELANDS PECULIARISED PECULIARIZED
PEDANTOCRACY PEDANTOCRATS PEDIATRICIAN PEDICELLARIA PENTACRINOID
PENTAHEDRONS PENTAHYDRATE PERACIDITIES PERADVENTURE PERAMBULATED
PERDURATIONS PEREGRINATED PERICARDITIC PERICARDITIS PERICARDIUMS
PERICHONDRAL PERICHONDRIA PERICLITATED PERIODICALLY PERIODONTIAS
PERLUSTRATED PEROXIDATION PERSEVERATED PERSONALISED PERSONALIZED
PETRODOLLARS PHELLODERMAL PHILANDERERS PHILANDERING PHOSPHORATED
PHOTOGRAPHED PLACEHOLDERS PLANTIGRADES PLASTERBOARD PLEURODYNIAS
PONDERANCIES PONDERATIONS POSTCARDLIKE POSTGRADUATE POSTMERIDIAN
PRASEODYMIUM PREADJUSTING PREADMISSION PREADMITTING PREADULTHOOD
PREAMBULATED PREANNOUNCED PREAPPOINTED PREASSEMBLED PREAUDIENCES
PREBENDARIES PRECANCELLED PRECAUTIONED PRECEDENTIAL PRECIPITATED
PREDECEASING PREDEPARTURE PREDESIGNATE PREDESTINATE PREDIABETICS
PREDIALITIES PREDICAMENTS PREDICATIONS PREDISCHARGE PREDISPOSALS
PREDOCTORALS PREDOMINANCE PREDOMINANCY PREDOMINATED PREDOMINATES
PREDOMINATOR PREFIGURATED PREFORMATTED PREHARDENING PREHARVESTED
PREINSTALLED PREJUDICATED PREJUDICATES PREMEDICALLY PREMEDICATED
PREMEDICATES PREMEDITATED PREMEDITATES PREMEDITATOR PRENOMINATED
PREOCCUPATED PREORDAINING PREORDINANCE PREPAREDNESS PREPONDERANT
PREPONDERATE PREPROGRAMED PREPURCHASED PREQUALIFIED PREROGATIVED
PRESIDENTIAL PRESIGNALLED PREVARICATED PRIVATDOCENT PRIVATDOZENT
PROBOSCIDEAN PROCATHEDRAL PROCEDURALLY PROCTODAEUMS PRODIGALISED
PRODIGALISES PRODIGALIZED PRODIGALIZES PROLIFERATED PROMUSCIDATE
PROOFREADERS PROOFREADING PROPAEDEUTIC PROPAGANDISE PROPAGANDIZE
PROPANEDIOIC PROTRACTEDLY PROTUBERATED PROUDHEARTED PROVIDENTIAL
PRUDENTIALLY PRUSSIANISED PRUSSIANIZED PSEUDOGRAPHS PSEUDOGRAPHY
PSEUDOMARTYR PSEUDORANDOM PSEUDOSCALAR PTERIDOMANIA PTERODACTYLE
PTERODACTYLS PYRIDOXAMINE PYRITOHEDRAL QUADRAPLEGIA QUADRAPLEGIC
QUADRICEPSES QUADRIPLEGIA QUADRIPLEGIC QUADRUPLEXED QUADRUPLEXES
RADIOGRAPHED RADIOGRAPHER RADIOISOTOPE RADIOPHONIES RADIOSCOPIES
RADIOTHERAPY READAPTATION REAPPARELLED RECIPROCATED REDEMPTIONAL
REDISPLAYING REDUPLICATED REDUPLICATES REEMPHASISED REEMPHASIZED
RELANDSCAPED RELANDSCAPES REPRIMANDING REPRIVATISED REPRIVATIZED
REPROGRAMMED REPUDIATIONS REPUNCTUATED RESPONDENTIA RHABDOSPHERE
RHODODAPHNES ROPEDANCINGS SANDPAPERIER SANDPAPERING SCOLOPENDRAS
SCORPAENOIDS SCRAPERBOARD SHARECROPPED SHARPBENDERS SIDEROPENIAS
SLIPSTREAMED SPARKPLUGGED SPATTERDOCKS SPEARHEADING SPEEDREADING
SPERMATOCIDE SPERMATOZOID SPHEROIDALLY SPREADEAGLED SPREADSHEETS
STAIRSTEPPED STANDPATTERS STENOGRAPHED STEPDAUGHTER STEWARDSHIPS
SUBEPIDERMAL SUPERABOUNDS SUPERCHARGED SUPEREXALTED SUPERFETATED
SUPERHARDENS SUPERMUNDANE SUPERORDINAL SUPERPRAISED SUPERSEDABLE
SUPERSTARDOM SUPRAMUNDANE SWORDPLAYERS TEMPORALISED TEMPORALIZED
THUNDERCLAPS TRADESPEOPLE TRADESPERSON TRANSPIERCED TRANSPLANTED
TRANSPONDERS TRANSSHIPPED TRAPEZOHEDRA TREPIDACIOUS TREPIDATIONS
TREPIDATIOUS TRIADELPHOUS TRICUSPIDATE TROPICALISED TROPICALIZED
TRYPANOCIDES TRYPARSAMIDE UNAPPARELLED UNAPPROACHED UNCHAPERONED
UNDERDAMPERS UNDERLAPPING UNDERPASSION UNDERPAYMENT UNDERPLANTED
UNDERPLAYING UNDERPRAISED UNDERPRAISES UNDESPAIRING UNEXPURGATED
UNPARALLELED UNPARDONABLE UNPATRONISED UNPATRONIZED UNPERFORATED
UNPREPAREDLY UNPROCEDURAL UNPROCLAIMED UNPROGRAMMED UNREPROACHED
UPWARDNESSES VIDEOGRAPHER WATERPROOFED