There are 953 eleven-letter words containing A and 3S, https://www.bestwordlist.com/c/a/4/11letterwordswithasss.htm
ABSCISSIONS ABSINTHISMS ABSOLUTISES ABSOLUTISMS ABSOLUTISTS ABSTERSIONS
ABSTERSIVES ABUSIVENESS ACCESSARIES ACCESSORIES ACCESSORISE ACCESSORIUS
ACRIDNESSES ACTRESSIEST ACUTENESSES ADDRESSINGS ADEPTNESSES ADULTNESSES
ADULTRESSES ADVERSENESS ADVISEDNESS AEROSOLISES AGELESSNESS AGGRESSIONS
AGILENESSES AIMLESSNESS AIRLESSNESS AIRSICKNESS ALBATROSSES ALERTNESSES
ALGIDNESSES ALIENNESSES ALIKENESSES ALIVENESSES ALONENESSES ALOOFNESSES
AMBASSADORS AMOROUSNESS AMPLENESSES AMUSINGNESS AMUSIVENESS ANAESTHESES
ANAESTHESIS ANASTOMOSES ANASTOMOSIS ANCHORESSES ANESTHESIAS ANGRINESSES
ANTECESSORS ANTISEXISTS ANTSINESSES ANXIOUSNESS APARTNESSES APERTNESSES
APISHNESSES APOSIOPESES APOSIOPESIS APOSTATISES APOSTOLISES ARBITRESSES
ARCHERESSES ARDUOUSNESS ARTLESSNESS ARTSINESSES ASCETICISMS ASCLEPIASES
ASEPTICISES ASEPTICISMS ASHAMEDNESS ASKEWNESSES ASPARAGUSES ASPERSORIES
ASPIDISTRAS ASSAFETIDAS ASSAILMENTS ASSASSINATE ASSEMBLAGES ASSENTATORS
ASSENTIENTS ASSESSMENTS ASSESSORIAL ASSEVERATES ASSIBILATES ASSIDUITIES
ASSIDUOUSLY ASSIGNMENTS ASSIMILATES ASSISTANCES ASSOCIATORS ASSOILMENTS
ASSORTMENTS ASSUMPTIONS ASSUREDNESS ASSYTHMENTS ASTATICISMS ASYSTOLISMS
AUDITRESSES AUSTERENESS AUTHORESSES AUTOCROSSES AVIATRESSES AWARENESSES
AWELESSNESS AWESOMENESS AWFULNESSES BABIROUSSAS BACKCROSSES BACKSHISHES
BACKSLASHES BAGGINESSES BAKHSHISHES BAKSHEESHES BALKINESSES BALMINESSES
BANDINESSES BARMINESSES BASHAWSHIPS BASHFULNESS BASSOONISTS BASTARDISES
BASTARDISMS BASTNASITES BATTINESSES BAWDINESSES BEADINESSES BEAMINESSES
BEARGRASSES BEARISHNESS BEASTLINESS BENTGRASSES BESTIALISES BESTIALISMS
BLACKNESSES BLANDNESSES BLANKNESSES BLASTOCYSTS BLASTODISCS BLEAKNESSES
BLUEGRASSES BOARISHNESS BONNILASSES BRADYSEISMS BRASHNESSES BRAVENESSES
BROADNESSES BURSARSHIPS BUSHMASTERS BUSINESSMAN CADDISHNESS CAGEYNESSES
CALLOUSNESS CAMPINESSES CANNINESSES CANTINESSES CANVASSINGS CARIOUSNESS
CARNASSIALS CARSICKNESS CASSOLETTES CASSOWARIES CASSUMUNARS CASUISTRIES
CATTINESSES CATTISHNESS CAUCUSSINGS CAUSELESSLY CAUSTICNESS CEASELESSLY
CHANTRESSES CHAPRASSIES CHARINESSES CHEAPNESSES CHESSBOARDS CHOLESTASES
CHOLESTASIS CHRYSALISES CHUPRASSIES CIRCASSIANS CLASSICISED CLASSICISES
CLASSICISMS CLASSICISTS CLASSICIZES CLASSIFIEDS CLASSIFIERS CLEANNESSES
CLEARNESSES COASSISTING COATDRESSES COMPASSINGS COMPASSIONS CONFESSANTS
CORDGRASSES CRABGRASSES CRANKNESSES CRASSITUDES CRASSNESSES CRAZINESSES
CREATRESSES CROSSANDRAS CROSSCLAIMS CRYSTALISES CUIRASSIERS DAFFINESSES
DAILINESSES DAILYNESSES DAMPISHNESS DASTARDNESS DATEDNESSES DAZEDNESSES
DEACONESSES DEBARRASSES DEBASEDNESS DEERGRASSES DEGAUSSINGS DEPRESSANTS
DESALINISES DESISTANCES DESSIATINES DESSYATINES DIASKEUASTS DIASPORISTS
DISASSEMBLE DISASSEMBLY DISCUSSABLE DISCUSSANTS DISENSLAVES DISHWASHERS
DISPASSIONS DISPERSANTS DISPOSABLES DISPRAISERS DISSERTATES DISSHEATHES
DISSIMILARS DISSIPATERS DISSIPATORS DISSOCIATES DISSONANCES DISSUASIONS
DISSUASIVES DISTANTNESS DRAGONESSES DRESSGUARDS DRESSMAKERS DUNIWASSALS
DWARFNESSES DYSCRASITES DYSKINESIAS EAGERNESSES EARLINESSES EARNESTNESS
EASEFULNESS ECBLASTESES ECBLASTESIS ECCLESIASTS ECSTASISING ELASMOSAURS
ELASTICISES ELASTICNESS EMBARRASSES EMBASSADORS ENCOMPASSES ENTHUSIASMS
ENTHUSIASTS EPISPASTICS EPISTAXISES EQUALNESSES ESEMPLASIES ESOPHAGUSES
ESTABLISHES EVASIVENESS EXACTNESSES EXACTRESSES EXHAUSTLESS EXPRESSAGES
EXPRESSWAYS FADDINESSES FADDISHNESS FADEDNESSES FAINTNESSES FALSENESSES
FANCINESSES FANTASISERS FARMERESSES FASCIITISES FASHIONISTS FATALNESSES
FATTINESSES FATUOUSNESS FISSIPARISM FISSIPAROUS FLAKINESSES FOAMINESSES
FRAILNESSES FRANKNESSES FUSTIANISES FUSTIANISTS GABBINESSES GALLOWSNESS
GAMEYNESSES GAOLERESSES GASEOUSNESS GASPINESSES GASSINESSES GASTRITISES
GASTROSOPHS GAUDINESSES GAUNTNESSES GAUSSMETERS GAUZINESSES GAWKINESSES
GAWKISHNESS GESTALTISMS GESTALTISTS GHASTLINESS GHASTNESSES GLARINESSES
GLASSCLOTHS GLASSHOUSES GLASSMAKERS GLASSPAPERS GLAZINESSES GLOSSARISTS
GOATISHNESS GRANDNESSES GRAPINESSES GRASSCLOTHS GRASSCYCLES GRASSWRACKS
GRAVENESSES GREATNESSES GYMNASIASTS HAEMOSTASES HAEMOSTASIS HAGGISHNESS
HAIRINESSES HAMMINESSES HANDGLASSES HANDINESSES HANDPRESSES HANSARDISES
HAPLESSNESS HAPPINESSES HARASSMENTS HARDGRASSES HARDINESSES HARNESSLESS
HARSHNESSES HARVESTLESS HASSOCKIEST HASTINESSES HATLESSNESS HAWKISHNESS
HEADDRESSES HEADINESSES HEARTSEASES HEAVINESSES HEMOSTASIAS HISTOBLASTS
HOARINESSES HOMEOSTASES HOMEOSTASIS HOURGLASSES HUMANNESSES HUSBANDLESS
HYDRASTISES HYPOSTASISE ICONOSTASES ICONOSTASIS IDEALNESSES INANENESSES
INAPTNESSES INCRASSATES INSESSORIAL INSPISSATED INSPISSATES INSPISSATOR
INSTANTNESS INSULARISMS INSULINASES IRATENESSES ISINGLASSES ISOSEISMALS
JADEDNESSES JAILERESSES JAILORESSES JANISSARIES JANITRESSES JAZZINESSES
JEALOUSNESS JOUISSANCES KAISERSHIPS KICKSHAWSES KILOGAUSSES KNAVISHNESS
KNOTGRASSES LADDISHNESS LANKINESSES LARGENESSES LARKINESSES LARKISHNESS
LASTINGNESS LAUNDRESSES LAWLESSNESS LEAFINESSES LEAKINESSES LEARINESSES
LESBIANISMS LOAMINESSES LOATHNESSES LOCALNESSES LOSABLENESS LOYALNESSES
MAIDISHNESS MALTINESSES MANGINESSES MANLINESSES MANNISHNESS MASSASAUGAS
MASSINESSES MASSIVENESS MASSPRIESTS MASTERCLASS MASTERSHIPS MATELLASSES
MATEYNESSES MAWKISHNESS MAXIDRESSES MAZEDNESSES MEALINESSES MEASURELESS
MEATINESSES MEGAGAUSSES MESOSCAPHES MESSIAHSHIP MESSIANISMS METASTASISE
MISANALYSES MISANALYSIS MISANDRISTS MISASSAYING MISASSEMBLE MISASSIGNED
MISASSUMING MISBIASSING MISCLASSIFY MISCLASSING MISEMPHASES MISEMPHASIS
MISMEASURES MISOGAMISTS MISSALETTES MUSICALISES MUSICALNESS MUTESSARIFS
NAIVENESSES NAKEDNESSES NANOGRASSES NAPPINESSES NARCISSISMS NARCISSISTS
NARCISSUSES NASTINESSES NATTINESSES NECESSAIRES NECESSARIES NEWSCASTERS
NEWSFLASHES NONPASSIVES NOSTALGISTS NYSTAGMUSES OBSESSIONAL OSTEOBLASTS
OSTEOCLASES OSTEOCLASIS OSTEOCLASTS OSTRACISERS OUTGASSINGS OUTPASSIONS
OVERASSERTS OVERCLASSES OVERGRASSES PAINTRESSES PALIMPSESTS PANCOSMISMS
PANDERESSES PANSOPHISMS PANSOPHISTS PANTDRESSES PARASITISES PARASITISMS
PARASITOSES PARASITOSIS PARLOUSNESS PASSAGEWAYS PASSAMEZZOS PASSIFLORAS
PASSIMETERS PASSIONATES PASSIONLESS PASSIVENESS PASSIVITIES PASTELLISTS
PASTEURISES PASTEURISMS PASTINESSES PASTORSHIPS PASTURELESS PATISSERIES
PATRONESSES PAUPERESSES PAUSELESSLY PAWKINESSES PEAKINESSES PEARTNESSES
PERISTALSES PERISTALSIS PERSUASIONS PERSUASIVES PETRISSAGES PHARISAISMS
PIANISSIMOS PIPSISSEWAS PISSASPHALT PLAINNESSES PLANENESSES PLASMODESMS
PLASMOLYSES PLASMOLYSIS PLASMOSOMES PLASTICISES PLESIOSAURS PLUMASSIERS
POSSESSABLE POSTCLASSIC POSTMASTERS POSTSEASONS PREFASCISTS PRELATESSES
PRESSBOARDS PROLAPSUSES PROSAICISMS PROSAICNESS PROSTATISMS PRUSSIANISE
PSALMODISES PSALMODISTS PSALTRESSES PSITTACOSES PSITTACOSIS PSYCHOGASES
PUISSAUNCES QUAKINESSES RABIDNESSES RAFFISHNESS RAININESSES RAMMISHNESS
RANDINESSES RANGINESSES RAPIDNESSES RASPINESSES RATTINESSES RAUCOUSNESS
RAYLESSNESS READDRESSES READINESSES REASSEMBLES REASSESSING REGALNESSES
REPOUSSAGES RESISTANCES RHAPSODISES RHAPSODISTS RICEGRASSES RURALNESSES
SABLEFISHES SACAHUISTAS SACAHUISTES SACCHARASES SACCHARISES SACCHAROSES
SACHEMSHIPS SAGEBRUSHES SAINTLINESS SALABLENESS SALERATUSES SALESCLERKS
SALESLADIES SALESPERSON SALICYLISMS SALMANASERS SALSUGINOUS SALTINESSES
SALTISHNESS SALTSHAKERS SAMARSKITES SAMEYNESSES SANDCASTLES SANDGLASSES
SANDGROUSES SANDINESSES SANDSUCKERS SANGIOVESES SANITARISTS SANSEVERIAS
SAPIDNESSES SAPLESSNESS SAPPINESSES SARCOCYSTIS SARCOIDOSES SARCOIDOSIS
SARCOPLASMS SARKINESSES SARTORIUSES SASQUATCHES SASSAFRASES SASSINESSES
SATEDNESSES SATISFICERS SAUCINESSES SAUSSURITES SAUSSURITIC SAVABLENESS
SAVOURINESS SAVVINESSES SAWDUSTIEST SCABBEDNESS SCALDFISHES SCALINESSES
SCANDALISES SCANTNESSES SCARINESSES SCHALSTEINS SCHEMATISES SCHEMATISMS
SCHEMATISTS SCHISMATICS SCHISMATISE SCHOLASTICS SCINTISCANS SCISSORTAIL
SCRAGGINESS SCRAPPINESS SCRATCHLESS SCRAWNINESS SCREENCASTS SCRIMSHANKS
SEAMANSHIPS SEAMINESSES SEAMSTRESSY SEASICKNESS SECESSIONAL SECULARISES
SECULARISMS SECULARISTS SEISMOGRAMS SEISMONASTY SEMICLASSIC SEMINARISTS
SEMIPOSTALS SENSUALISED SENSUALISES SENSUALISMS SENSUALISTS SENSUALIZES
SENSUALNESS SEPARATISMS SEPARATISTS SERRASALMOS SERVANTLESS SESSIONALLY
SEXTARIUSES SHADINESSES SHADOWCASTS SHADOWINESS SHAGGEDNESS SHAHTOOSHES
SHAKINESSES SHALLOWNESS SHAMELESSLY SHAPELESSLY SHAPELINESS SHARPNESSES
SHEATFISHES SHEEPSHANKS SHEEPSHEADS SHERARDISES SHINKANSENS SHIPMASTERS
SHIRTWAISTS SHOALNESSES SHOCKSTALLS SIDEROSTATS SIDESADDLES SINARCHISMS
SINARCHISTS SINARQUISMS SINARQUISTS SINSEMILLAS SIZABLENESS SKIASCOPIES
SKRIMSHANKS SKYSCRAPERS SLACKNESSES SLACTIVISMS SLACTIVISTS SLAISTERIES
SLATINESSES SLAVISHNESS SLIMNASTICS SLIPSTREAMS SMALLNESSES SMALLSWORDS
SMARTNESSES SMOKESTACKS SNAILFISHES SNAKEFISHES SNAKESTONES SNAKINESSES
SNAKISHNESS SOAPINESSES SOAPSUDSIER SOCIALISERS SOLIDARISMS SOLIDARISTS
SOMERSAULTS SOMESTHESIA SOOTHSAYERS SOUNDSCAPES SOUNDSTAGES SOUSAPHONES
SPACINESSES SPADEFISHES SPANIOLISES SPARENESSES SPARINGNESS SPARKLESSLY
SPASMODISTS SPATIALISES SPEAKEASIES SPEARFISHES SPECIALISES SPECIALISMS
SPECIALISTS SPECIALNESS SPECTATRESS SPESSARTINE SPESSARTITE SPHACELUSES
SPINCASTERS SPINMASTERS SPIRALISERS SPLASHBACKS SPLASHDOWNS SPLASHINESS
SPOKESHAVES SPORTSCASTS SPORTSWEARS SQUABASHERS SQUADOOSHES SQUALIDNESS
SQUASHINESS SQUATNESSES SQUATTINESS SQUAWBUSHES SQUAWFISHES SQUEAKINESS
STABILISERS STAGINESSES STAIDNESSES STAINLESSES STAINLESSLY STALENESSES
STANDFIRSTS STANDSTILLS STAPEDIUSES STARCHINESS STARKNESSES STATEHOUSES
STATELINESS STATOBLASTS STATOSCOPES STAUNCHLESS STAUNCHNESS STAVESACRES
STEAKHOUSES STEARSMATES STEATOLYSES STEATOLYSIS STEENBRASES STEERSMATES
STEGOSAURUS STIBIALISMS STIGMATISES STIGMATISMS STIGMATISTS STOICALNESS
STOMACHLESS STONEMASONS STONEWASHES STRANGENESS STRAPLESSES STRATEGISES
STRATEGISTS STRATHSPEYS STREAKINESS STREAMINESS STREAMSIDES STRIPTEASES
SUASIVENESS SUAVENESSES SUBACIDNESS SUBASSEMBLE SUBASSEMBLY SUBCLASSIFY
SUBCLASSING SUBSTATIONS SUBSTRATUMS SUBSURFACES SUCCESSORAL SUCCOTASHES
SUCCURSALES SUFFISANCES SUFFRAGISMS SUFFRAGISTS SUGARBUSHES SUGARHOUSES
SULPHATASES SULTANESSES SULTANSHIPS SUMMARINESS SUMMARISERS SUPERSAVERS
SUPERSCALES SUPERSEDEAS SUPERSTATES SUPERVISALS SUPPRESSANT SURFACELESS
SURFCASTERS SURPASSABLE SURPLUSAGES SURREALISMS SURREALISTS SUSPENSORIA
SUSTAININGS SUSTENANCES SUSTENTATES SWARTHINESS SWARTNESSES SWEATSHIRTS
SWEEPSTAKES SWITCHGRASS SYBARITISMS SYMPATHISES SYMPOSIASTS SYNANTHESES
SYNANTHESIS SYNESTHESIA SYNSEPALOUS SYNTHETASES SYSSARCOSES SYSSARCOSIS
SYSSARCOTIC SYSTEMATICS SYSTEMATISE SYSTEMATISM SYSTEMATIST TACITNESSES
TACKINESSES TAILORESSES TALKINESSES TALLGRASSES TANGINESSES TAPERNESSES
TAPSTRESSES TARANTASSES TARDINESSES TARRINESSES TARTINESSES TASKMASTERS
TASSELLIEST TASSELLINGS TASTELESSLY TASTINESSES TATTINESSES TAWNINESSES
TEARINESSES TESSELLATES THALASSIANS THESAURUSES TICKLEASSES TOADGRASSES
TRAITRESSES TRANSFUSERS TRANSISTORS TRANSPOSALS TRANSPOSERS TRANSPOSONS
TRANSSHAPES TRANSVERSES TRESPASSERS TRESPASSING TSESAREVNAS TSOTSITAALS
TURFGRASSES TYRANNESSES TYROSINASES UNAPTNESSES UNASSISTING UNBIASSINGS
UNCLASSIEST UNDERPASSES UNHARNESSES UNSHARPNESS UNSTAIDNESS UNSURPASSED
UNUSUALNESS USEABLENESS USUALNESSES VACUOUSNESS VAGUENESSES VALIDNESSES
VANTBRASSES VAPIDNESSES VARIOUSNESS VARLETESSES VASOPRESSIN VASOPRESSOR
VASOSPASTIC VASSALESSES VASSALISING VERNISSAGES VISUALISERS VITALNESSES
VOCALNESSES WACKINESSES WAGGISHNESS WASHINESSES WASPINESSES WASPISHNESS
WASSAILINGS WASSAILRIES WASTENESSES WATERBUSSES WEAKISHNESS WEARINESSES
WHITEBASSES WINEGLASSES WIREGRASSES WOMANNESSES ZEALOUSNESS