Mammoth Uncensored Word List:
64 - 13 letter words starting with as

ascensionists ascertainable ascertainably ascertainment ashamednesses asparaginases aspergilloses aspergillosis aspheterising aspheterizing asphyxiations assassinating assassination assassinators assemblagists assemblaunces assemblywoman assemblywomen assentiveness assertiveness assessorships asseverations assibilations assiduousness assignability assimilations assistantship associability associateship associational associatively associativity assortatively assubjugating assuefactions assurednesses astacological astacologists astereognoses astereognosis asthenosphere asthmatically astonishingly astonishments astrapophobes astrapophobia astrapophobic astringencies astrobotanies astrochemical astrochemists astrocytomata astrodynamics astrogeologic astrometrical astronautical astronomising astronomizing astrophysical astrotourisms astrotourists asymtotically asynchronisms asyndetically