Mammoth Uncensored Word List:
18 - 18 letter words starting with an

anagrammatizations anarchosyndicalism anarchosyndicalist aneurysmorrhaphies angiocardiographic angiostrongyliasis anthropocentricity anthropomorphising anthropomorphizing antiadministration anticholinesterase anticommercialisms anticonstitutional anticounterfeiting antidiscrimination antiferromagnetism antiinflammatories antivivisectionist