There are 749 thirteen-letter words containing A, F and N, https://www.bestwordlist.com/c/a/3/13letterwordswithafn.htm
ABORTIFACIENT ACETIFICATION ACIDIFICATION AERIFICATIONS AFFECTIONALLY
AFFECTIONLESS AFFECTIVENESS AFFENPINSCHER AFFORESTATION AFFRANCHISING
AFFREIGHTMENT AFFRIGHTENING AFFRIGHTMENTS AFTERBURNINGS AIRCRAFTWOMAN
AIRCRAFTWOMEN AIRFREIGHTING ALUMINIFEROUS AMPLIFICATION ANFRACTUOSITY
ANTENNIFEROUS ANTIAIRCRAFTS ANTIFEMINISMS ANTIFEMINISTS ANTIFERTILITY
ANTIFOREIGNER ANTIFORMALISM ANTIFORMALIST AQUAFITNESSES ARFVEDSONITES
ARGENTIFEROUS ASSUEFACTIONS ASTROTURFINGS AUTOINFECTION BACKFLIPPINGS
BALEFULNESSES BANEFULNESSES BAREFACEDNESS BASHFULNESSES BASIFICATIONS
BEATIFICATION BEAUTIFULNESS BENEFICENTIAL BENEFICIARIES BENEFICIATING
BENEFICIATION BIOFLAVONOIDS BIOINFORMATIC BLANKETFLOWER BLUESNARFINGS
BRANFULNESSES BRASSFOUNDERS BRASSFOUNDING BREASTFEEDING CALCIFICATION
CANDLESNUFFER CAPRIFICATION CARBONIFEROUS CAREFULNESSES CARNIFICATION
CENTRIFUGALLY CERTIFICATING CERTIFICATION CHANGEFULNESS CHIEFTAINCIES
CHIEFTAINRIES CHIEFTAINSHIP CHYLIFICATION CHYMIFICATION CIPROFLOXACIN
CITIFICATIONS CITYFICATIONS CLARIFICATION CLIFFHANGINGS COALIFICATION
CODIFICATIONS COLORFASTNESS COMPACTIFYING CONFABULATING CONFABULATION
CONFABULATORS CONFABULATORY CONFARREATION CONFECTIONARY CONFEDERACIES
CONFEDERATING CONFEDERATION CONFEDERATIVE CONFESSIONALS CONFESSIONARY
CONFIGURATING CONFIGURATION CONFIGURATIVE CONFIGURATORS CONFIRMATIONS
CONFISCATABLE CONFISCATIONS CONFLAGRATING CONFLAGRATION CONFLAGRATIVE
CONFORMATIONS CONFRATERNITY CONFRONTATION CONFUSABILITY CONTRAFAGOTTI
CONTRAFAGOTTO COREFERENTIAL CORNIFICATION COSURFACTANTS COTRANSFERRED
COUNTERSHAFTS CRAFTMANSHIPS CRAFTSMANLIKE CRAFTSMANSHIP CRAFTSPERSONS
CRESTFALLENLY CYCLOPARAFFIN DAMNIFICATION DANDIFICATION DECAFFEINATED
DECAFFEINATES DECLASSIFYING DECRASSIFYING DEFENESTRATED DEFENESTRATES
DEFERENTIALLY DEFEUDALISING DEFEUDALIZING DEFIANTNESSES DEFIBRINATING
DEFIBRINATION DEFLAGRATIONS DEFLATIONISTS DEFLOCCULANTS DEFORCIATIONS
DEFORESTATION DEFORMALISING DEFORMALIZING DEFORMATIONAL DEFRAGMENTERS
DEFRAGMENTING DEFRAUDATIONS DELIRIFACIENT DENSIFICATION DESANCTIFYING
DESULFURATING DESULFURATION DIBENZOFURANS DIEFFENBACHIA DIFFARREATION
DIFFERENTIALS DIFFERENTIATE DIFUNCTIONALS DIGNIFICATION DISAFFECTIONS
DISAFFIRMANCE DISFIGURATION DISFRANCHISED DISFRANCHISES DISFUNCTIONAL
DISINFECTANTS DISINFESTANTS DISINFLATIONS DISQUALIFYING DISSATISFYING
DRAFTSMANSHIP DRAFTSPERSONS DULCIFICATION DYSFUNCTIONAL EASEFULNESSES
EFFECTUALNESS EFFECTUATIONS EFFIGURATIONS ENFRANCHISERS ENFRANCHISING
ENGRAFTATIONS EXFILTRATIONS EXSUFFLATIONS FACETIOUSNESS FACILITATIONS
FACTIONALISED FACTIONALISES FACTIONALISMS FACTIONALISTS FACTIONALIZED
FACTIONALIZES FACTORISATION FACTORIZATION FACTUALNESSES FADDISHNESSES
FAIRNITICKLES FAIRNYTICKLES FAITHLESSNESS FALSIFICATION FAMILIARISING
FAMILIARIZING FANATICALNESS FANFARONADING FANTASMICALLY FANTASTICALLY
FANTASTICATED FANTASTICATES FANTASTICISMS FARADISATIONS FARADIZATIONS
FARAWAYNESSES FARNARKELINGS FARTHINGLANDS FASCICULATION FASCINATINGLY
FASHIONMONGER FATEFULNESSES FATHEADEDNESS FATIGABLENESS FATUOUSNESSES
FAULTFINDINGS FAULTLESSNESS FAUNISTICALLY FAVORABLENESS FAVOREDNESSES
FAWNINGNESSES FEARFULNESSES FEARMONGERING FEATHERBRAINS FEATHEREDGING
FEBRIFACIENTS FELICITATIONS FEMINISATIONS FEMINIZATIONS FENESTRATIONS
FENFLURAMINES FERMENTATIONS FERRICYANIDES FERRICYANOGEN FERRIMAGNETIC
FERROCYANIDES FERROCYANOGEN FERROMAGNETIC FERTILISATION FERTILIZATION
FETISHISATION FETISHIZATION FEUDALISATION FEUDALIZATION FIANCHETTOING
FIBERGLASSING FIBERISATIONS FIBERIZATIONS FIBREGLASSING FIBRILLATIONS
FICTIONALISED FICTIONALISES FICTIONALIZED FICTIONALIZES FILTRABLENESS
FINABLENESSES FINALISATIONS FINALIZATIONS FINANCIALISTS FINGERBREADTH
FINGERGLASSES FINICALNESSES FLABELLATIONS FLACCIDNESSES FLAGELLANTISM
FLAGELLATIONS FLAGELLOMANIA FLAMBOYANCIES FLAMEPROOFING FLAMMULATIONS
FLANNELBOARDS FLANNELGRAPHS FLASHMOBBINGS FLAUNTINESSES FLAVOPROTEINS
FLAVOPURPURIN FLOCCILLATION FLOCCULATIONS FLOWCHARTINGS FLUCTUATIONAL
FLUIDISATIONS FLUIDIZATIONS FLUNITRAZEPAM FLUORIDATIONS FLUORINATIONS
FLUOROCARBONS FLUPHENAZINES FOCALISATIONS FOCALIZATIONS FONCTIONNAIRE
FOOLHARDINESS FOOTDRAGGINGS FORAMINIFERAL FORAMINIFERAN FOREGATHERING
FORENSICALITY FOREORDAINING FORESHADOWING FORESTALLINGS FORESTALLMENT
FORESTALMENTS FORETRIANGLES FOREWARNINGLY FORMALISATION FORMALIZATION
FORMATIVENESS FORMULARISING FORMULARIZING FORTEPIANISTS FORTIFICATION
FORTUNATENESS FORWARDNESSES FOSSILISATION FOSSILIZATION FOUNDATIONARY
FOUNDATIONERS FOUNTAINHEADS FRACTIONALISE FRACTIONALISM FRACTIONALIST
FRACTIONALIZE FRACTIONATING FRACTIONATION FRACTIONATORS FRACTIONISING
FRACTIONIZING FRACTIOUSNESS FRAGILENESSES FRAGMENTARILY FRAGMENTATING
FRAGMENTATION FRAGMENTISING FRAGMENTIZING FRANCHISEMENT FRANCISATIONS
FRANCIZATIONS FRANCOPHOBIAS FRANGIBLENESS FRANKALMOIGNS FRANKINCENSES
FRANTICNESSES FRATERNALISMS FRAUDULENCIES FREEMASONRIES FREQUENTATION
FREQUENTATIVE FRESHMANSHIPS FRIABLENESSES FROWARDNESSES FRUITARIANISM
FRUMENTACEOUS FRUMENTARIOUS FRUMENTATIONS FRUSTRATINGLY FUGACIOUSNESS
FUNAMBULATING FUNAMBULATION FUNAMBULATORS FUNAMBULATORY FUNCTIONALISM
FUNCTIONALIST FUNCTIONALITY FUNCTIONARIES FUNCTIONATING FUNDAMENTALLY
FURACIOUSNESS FURAZOLIDONES FUSTILLIRIANS FUTILITARIANS GAINFULNESSES
GAMIFICATIONS GARNETIFEROUS GASIFICATIONS GEMEINSCHAFTS GIFTWRAPPINGS
GLADFULNESSES GLORIFICATION GRANDFATHERED GRANDFATHERLY GRANULIFEROUS
GRATIFICATION HANDCRAFTSMAN HANDCRAFTSMEN HANDICRAFTERS HANDKERCHIEFS
HARMFULNESSES HASENPFEFFERS HATEFULNESSES HEALTHFULNESS HENCEFORWARDS
HERPETOFAUNAE HERPETOFAUNAS HIGHFALUTINGS HONORIFICALLY HORRIFICATION
HUMIFICATIONS HYPERINFLATED ICHTHYOFAUNAE ICHTHYOFAUNAL ICHTHYOFAUNAS
IMMUNIFACIENT IMPERFORATION INDEFATIGABLE INDEFATIGABLY INEFFABLENESS
INEFFECTUALLY INEFFICACIOUS INFALLIBILISM INFALLIBILIST INFALLIBILITY
INFANTILISING INFANTILITIES INFANTILIZING INFEASIBILITY INFERENTIALLY
INFERNALITIES INFIBULATIONS INFILTRATIONS INFINITESIMAL INFINITIVALLY
INFLAMMATIONS INFLATIONISMS INFLATIONISTS INFLEXIONALLY INFLUENCEABLE
INFLUENTIALLY INFORMALITIES INFORMATICIAN INFORMATIONAL INFORMATISING
INFORMATIVELY INFORMATIZING INFORMATORILY INFOTAINMENTS INFRAPOSITION
INFRASPECIFIC INFUNDIBULATE INFURIATINGLY INGRAFTATIONS INSIGNIFICANT
INSUFFLATIONS INTERFACIALLY INTERFAMILIAL INTERFEROGRAM INTERFOLIATED
INTERFOLIATES INTERGRAFTING INTERSTRATIFY INTERTRAFFICS INTRASPECIFIC
IRREFRANGIBLE IRREFRANGIBLY JALOALLOFANES JELLIFICATION JOLLIFICATION
JUSTIFICATION LABEFACTATION LIGHTFASTNESS LIGNIFICATION LIQUEFACIENTS
LIQUEFACTIONS LIQUIFACTIONS LITHIFICATION MAGNIFICATION MAGNIFICENCES
MAGNIFICENTLY MALFORMATIONS MALFUNCTIONED MANGANIFEROUS MANIFESTATION
MANIFESTATIVE MANUFACTORIES MANUFACTURERS MANUFACTURING MASSIFICATION
MASTERFULNESS MELLIFICATION METAFICTIONAL METRIFICATION MICROFILAMENT
MICROFINANCES MIDAFTERNOONS MINIFICATIONS MISFORMATIONS MISINFORMANTS
MODIFICATIONS MOLLIFICATION MONOFILAMENTS MORTIFICATION MULTIFILAMENT
MUMMIFICATION MUNDIFICATION MUNDIFICATIVE MYSTIFICATION NAZIFICATIONS
NECTARIFEROUS NEFARIOUSNESS NEUROFEEDBACK NEUROFIBRILAR NEUROFIBROMAS
NEWFANGLENESS NIDIFICATIONS NITRIFICATION NITROPARAFFIN NONAFFILIATED
NONCLASSIFIED NONCOLOURFAST NONDEFERRABLE NONFIGURATIVE NONFILTERABLE
NONFLAMMABLES NONFUNCTIONAL NONMEANINGFUL NONREFILLABLE NONREFUNDABLE
NOTIFICATIONS NULLIFICATION OFFHANDEDNESS OMNIFARIOUSLY OSSIFICATIONS
OVERFATIGUING OVERFAVOURING OVERINFLATING OVERINFLATION OVERSTAFFINGS
PACIFICATIONS PAINFULNESSES PALIFICATIONS PALMIFICATION PANIFICATIONS
PARAINFLUENZA PARFOCALISING PARFOCALIZING PASSIONFLOWER PERFECTATIONS
PERFECTIONATE PERFOLIATIONS PERSONIFIABLE PETRIFACTIONS PETRIFICATION
PLATINIFEROUS PLAYFULNESSES PLEBIFICATION PONTIFICALITY PONTIFICATING
PONTIFICATION PONTIFICATORS PORNIFICATION PRAYERFULNESS PREACHIFYINGS
PREFIGURATING PREFIGURATION PREFINANCINGS PREFLORATIONS PREFOLIATIONS
PREFORMATIONS PREFORMATTING PREQUALIFYING PRESANCTIFIED PRESANCTIFIES
PROFANENESSES PROFESSIONALS PROLIFERATING PROLIFERATION PROLIFICATION
PROOFREADINGS PURIFICATIONS PUTREFACTIONS PUTRIFICATION QUALIFICATION
QUARTERFINALS RAFFISHNESSES RAMIFICATIONS RANGEFINDINGS RAREFACTIONAL
RAREFICATIONS RATIFICATIONS REAFFIRMATION REAFFORESTING RECLASSIFYING
RECTIFICATION REFASHIONMENT REFERENDARIES REFERENTIALLY REFOCILLATING
REFOCILLATION REFORESTATION REFORMATIONAL REFORMULATING REFORMULATION
REFOUNDATIONS REFRIGERATING REFRIGERATION REFUNDABILITY REGARDFULNESS
REINFESTATION REINFORCEABLE REMANUFACTURE RETRANSFERRED RETRANSFORMED
RETRANSFUSING REUNIFICATION SACCHARIFYING SAFECRACKINGS SALIFICATIONS
SANCTIFYINGLY SATISFACTIONS SCARIFICATION SCATHEFULNESS SCHADENFREUDE
SCORIFICATION SEMIFINALISTS SHAMEFASTNESS SHAPESHIFTING SHRINKFLATION
SIGNIFICANCES SIGNIFICANTLY SIGNIFICATION SIGNIFICATIVE SIGNIFICATORS
SIGNIFICATORY SLUMPFLATIONS SOLIFIDIANISM SOMNIFACIENTS SOOTHFASTNESS
SORBEFACIENTS SPECIFICATING SPECIFICATION SPIFFLICATING SPIFFLICATION
SPIFLICATIONS STAMINIFEROUS STANDOFFISHLY STEADFASTNESS STUPEFACIENTS
STUPEFACTIONS SUBFEUDATIONS SUBINFEUDATED SUBINFEUDATES SUFFOCATINGLY
SUFFRAGANSHIP SUFFUMIGATING SUFFUMIGATION SULFADIAZINES SULFADIMIDINE
SULFANILAMIDE SULFONMETHANE SULFONYLUREAS SULFORAPHANES SULFURISATION
SULFURIZATION SUPERFETATING SUPERFETATION SUPERFRONTALS SURFBOARDINGS
TABLESPOONFUL TACTFULNESSES TARIFFICATION TEARFULNESSES TERRAFORMINGS
TESTIFICATION THENCEFORWARD THOUSANDFOLDS THURIFICATION TORREFACTIONS
TRANSFECTIONS TRANSFERENCES TRANSFERRABLE TRANSFERRIBLE TRANSFIGURING
TRANSFORMABLE TRANSFORMINGS TRANSFORMISMS TRANSFORMISTS TRANSFUSIONAL
TRANSFUSIVELY TRIFURCATIONS TRUSTAFARIANS TRYPAFLAVINES TYPIFICATIONS
UGLIFICATIONS ULTRAFEMININE UNBEAUTIFULLY UNCOMFORTABLE UNCOMFORTABLY
UNCONFORMABLE UNCONFORMABLY UNDERFINANCED UNDERINFLATED UNDERSTAFFING
UNDERSURFACES UNENFORCEABLE UNFAILINGNESS UNFALSIFIABLE UNFALTERINGLY
UNFAMILIARITY UNFASHIONABLE UNFASHIONABLY UNFATHERLIEST UNFEUDALISING
UNFEUDALIZING UNFORESEEABLE UNFORESEEABLY UNFORGETTABLE UNFORGETTABLY
UNFORTUNATELY UNFULFILLABLE UNHEALTHFULLY UNINFLAMMABLE UNINFLUENTIAL
UNINFORCEABLE UNINFORMATIVE UNJUSTIFIABLE UNJUSTIFIABLY UNPERFORMABLE
UNQUALIFIABLE UNQUALIFIEDLY UNREPROACHFUL UNSANCTIFYING UNSATISFIABLE
UNSPECIFIABLE UNSTEADFASTLY UNTACTFULNESS UNTHRIFTIHEAD UNTHRIFTYHEAD
UNTRANSFORMED UNVITRIFIABLE VERBIFICATION VERIFICATIONS VERSIFICATION
VILIFICATIONS VINIFICATIONS VITRIFACTIONS VITRIFICATION VIVIFICATIONS
VOCIFERATIONS VOUCHSAFEMENT WAKEFULNESSES WASTERFULNESS WATERFLOODING
WATERFOWLINGS WATERPROOFING WINEGLASSFULS WOODCRAFTSMAN WOODCRAFTSMEN
YUPPIFICATION ZINCIFICATION ZINKIFICATION ZOMBIFICATION